ML13085A400

Transmittal of Technical Specifications Amendment 18

ML13085A400
Person / Time
Site:	North Carolina State University
Issue date:	02/13/2013
From:	Hawari A North Carolina State University
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML13085A400 (125)

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North Carolina State University is a land- Nuclear Reactor Program Grant university and a constituent institution Of The University of North Carolina I NCSTT An Equal Opportunity/Affirmative Action Employer Nuclear Reactor Program Campus Box 7909 Raleigh, North Carolina 27695 http://www.ne.ncsu.edu/nrp/index.html Director 919.515.4598 Office 919.515.7294 (Fax) 919.513.1276 Shipping Address:

NC State University 2500 Stinson Dr.

Raleigh, NC 27695 13 Feb 2013 US Nuclear Regulat(ory Commission Document Control E)esk Washington, DC Re: Technical Specif ications Amendment 18 License No. R-1 20 Docket No. 50-2 97 Attached please find Amendment 18 to the facility Technical Specifications. Technical Specification (TS) 3..8 was revised as described in Attachment 1. If Amendment 18 is approved, informatic)n from Attachment 1 will replace the existing fueled experiment analysis in the Safety(Analysis Report.

If you have any ques tions regarding this amendment or require additional information, please contact Gerald Wick sat 919-515-4601 or wickskncsu.edu.

I declare under penalIty of perjury that the forgoing is true and correct. Executed on 13 Feb 2013.

Sincerely, Ayman I. Hawari, P1h.D.

Director, Nuclear Re,actor Program North Carolina State University

Enclosures:

T echnical Specification Amendment 18 Attachment 1: Fueled Experiment Analysis cc: Duane Hardesty, US NRC

Summary TS 3.8 regarding fueled experiments has been modified for conducting experiments using any fissionable material based on limiting doses to less than 10 percent of the applicable limits for members of the public and occupational workers.

Fission of thirty fissionable materials was analyzed with release of the fission products to the reactor building air space. Fissionable materials were placed in two categories; (1) Isotopes of U and Pu and (2) All Others. U'and Pu were placed in a separate category since various isotopic enrichments of these elements are commonly used. Continuous irradiation times up to 1 year followed by decay times up to 1 year were evaluated for wet and dry conditions.

Total effective dose-equivalent for members of the public is limited to 0.01 rem and total effective dose-equivalent and committed dose-equivalent to the thyroid for occupationally exposed workers are limited to 0.5 rem and 5 rem, respectively. These dose limitations are consistent with the TS 3.8 used in Amendment 17.

Up to 10% of the applicable dose limits is a reasonable limitation based on the requirements given in 10 CFR 20 for monitoring of occupational personnel and reporting doses in excess of the constraint dose for members of the public. This limitation meets guidance given in Regulatory Guide 2.2 "Development of Technical Specifications for Experiments in Research Reactors". Also the proposed limit of 10 percent of the annual public dose limit, or 0.01 rem, is well below the dose associated with the "Notification of Unusual Event" emergency declaration.

Attachment 1 provides details on the fueled experiment analysis. Revision of TS 3.8 for Amendment 18 was based on the analysis provided in Attachment 1.

The analysis made in Attachment I uses independent fission yields rather than cumulative fission yields as was done in Amendment 17. As a result of the fission yields used and additional fissionable materials analyzed, the proposed TS 3.8 in Amendment 18 has different fission rates associated with the dose limitations. Power levels produced in the experiment, mass limits, and mass-fluence given in TS 3.8 in Amendment 17 have been deleted in Amendment 18. To meet the fission rate limits listed in Amendment 18, the mass of the fissionable material is determined from the listed fission rate, fission cross-section, and fluence rate. Other conditions in Amendment 18 are the same as those given in Amendment 17.

Activities calculated in TS 18 are a better approximation of the actual activities being produced in fissionable materials than that used in TS 17. TS 17 used cumulative fission yields and TS 18 used individual fission yields with a time dependent activity buildup from production and decay.

The activity calculations made by this method in TS 18 are generally higher than those estimated by the Nuclear Analysis 1.0 program.

The associated limiting fission rates in TS 18 are higher than those in TS 17, but are explained by the difference in the calculation model used. With this explanation and with activity results being generally greater than those from an independent computer based program, the resulting limiting fission rates determined in TS 18 are concluded to be acceptable for fueled experiments.

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Summary of Changes to Technical Specifications Amendment 18 Table of Contents on pages i and ii:

Page numbers were updated for the revised Specification 3.8 and associated tables and figures.

Specification 3.8 on pages 26 - 31:

Fueled experiments are defined in Technical Specifications (TS) as experiments that contain fissionable material. TS 3.8 on fueled experiments in Amendment 17 limits fueled experiments to those that contain only U-235. Numerous fissionable materials were analyzed in support of TS Amendment 18 to provide limiting conditions for two categories of fissionable materials; (1)

U and Pu and (2) All Others. U and Pu are placed in a separate category since various isotopic enrichments of these elements are commonly used.

3.8.a Mass and power limitations were deleted. Fission rates were used as the limiting factor since activity produced is directly related to the fission rate within the sample.

Specification was reworded for fission rate limits for isotopes of (i) U and Pu and (ii) all other fissionable materials. Figures and tables for the two categories of fissionable materials were added:

i. Figure 3.8-1 and Table 3.8-1 for isotopes of U and Pu ii. Figure 3.8-2 and Table 3.8-2 for all other fissionable materials 3.8.e.v Because the reactor confinement system is needed during sample irradiation to mitigate the potential release of radioactive fission products, this condition was added to require the sample to be irradiated and unloaded within the reactor building.

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Appendix A Technical Specifications for the North Carolina State University PULSTAR Reactor Facility License No. R-120 Docket No. 50-297 Amendment 18

Appendix A Amendment 18 Technical Specifications TABLE OF CONTENTS 1.0. INTRODUCTION 1 1.1. Purpose ............................................................................................................................ 1 1.2. D efinitions ....................................................................................................................... 1 2.0. SAFETY LIMITS AND LIMITING SAFETY SYSTEM SETTINGS 7 2.1. Safety Lim its (SL) ........................................................................................................ 7 2.2. Lim iting Safety System Settings ............................................................................. 11 3.0. LIMITING CONDITIONS FOR OPERATION 13 3.1. Reactor Core Configuration ..................................................................................... 13 3.2. Reactivity ...................................................................................................................... 14 3.3. Reactor Safety System .............................................................................................. 16 3.4. Reactor Instrum entation ............................................................................................ 18 3.5. Radiation M onitoring Equipm ent ............................................................................ 19 3.6. Confinem ent and M ain HV A C System s ................................................................... 21 3.7. Lim itations of Experim ents ...................................................................................... 23 3.8. Operations w ith Fueled Experim ents ........................................................................ 26 3.9. Prim ary Coolant ....................................................................................................... 32 4.0. SURVEILLANCE REQUIREMENTS 33 4 .1. F u e l ............................................................................................................................... 33 4.2. Control Rods ................................................................................................................. 34 4.3. Reactor Instrum entation and Safety System s ............................................................. 36 4.4. Radiation M onitoring Equipm ent ............................................................................ 37 4.5. Confinem ent and Main HV A C System ................................................................... 38 4.6. Prim ary and Secondary Coolant ............................................................................... 39 5.0. DESIGN FEATURES 40 5.1. Reactor Fuel .................................................................................................................. 40 5.2. Reactor Building ....................................................................................................... 40 5.3. Fuel Storage .................................................................................................................. 40 5.4. Reactivity Control ..................................................................................................... 41 5.5. Prim ary Coolant System .......................................................................................... 41 6.0. ADMINISTRATIVE CONTROLS 43 6.1. Organization .................................................................................................................. 43 6.2. Review and A udit ..................................................................................................... 48 6.3. Radiation Safety ........................................................................................................ 51 6.4. Operating Procedures ................................................................................................. 52 6.5. Review of Experim ents ............................................................................................ 53 6.6. Required Actions ..................................................................................................... 54 6.7. Reporting Requirem ents ............................................................................................ 55 6.8. Retention of Records ................................................................................................. 58 i

Appendix A Amendment 18 Technical Specifications FIGURES Figure 2.1-1: Power-Flow Safety Lim it Curve .......................................................................... 9 Figure 3.8-1: Fueled Experiment Limiting Fission Rate for Isotope of U and Pu .................... 27 Figure 3.8-2: Fueled Experiment Limiting Fission Rate for All Other Fissionable Materials ..... 29 Figure 5.2-1: NCSU PULSTAR Reactor Site Map ................................................................ 42 Figure 6.1-1: NCSU PULSTAR Reactor Organizational Chart .............................................. 47 TABLES Table 3.2-1: Reactivity Lim its for Experim ents ..................................................................... 14 Table 3.3-1: Required Safety and Safety Related Channels ................................................... 16 Table 3.5-1: Required Radiation Area Monitors ..................................................................... 19 Table 3.6-1: Required Main HVAC and Confinement Conditions ......................................... 21 Table 3.8-1: Limiting Fission Rates for Isotopes of U and Pu ................................................. 28 Table 3.8-2: Limiting Fission Rates for All Other Fissionable Materials ............................... 30 ii

Appendix A Amendment 18 Technical Specifications 1.0. INTRODUCTION 1.1. Purpose These Technical Specifications provide limits within which operation of the reactor will assure the health and safety of the public, the environment and on-site personnel. Areas addressed are Definitions, Safety Limits (SL), Limiting Safety System Settings (LSSS), Limiting Conditions for Operation (LCO), Surveillance Requirements, Design Features, and Administrative Controls.

Included in this document are the "Bases" for the Technical Specifications. The bases provide the technical support for the individual technical specification and are included for information purposes only. The bases are not part of the Technical Specifications, and they do not constitute limitations or requirements to which the licensee must adhere.

1.2. Definitions

1.2.1. Channel

A channel is the combination of sensor, line, amplifier, and output devices which are connected for the purpose of measuring the value of a parameter.

1.2.2. Channel Calibration: A channel calibration is an adjustment of the channel, such that its output corresponds with acceptable accuracy to known values of the parameter that the channel measures. Calibration shall encompass the entire channel, including equipment actuation, alarm or trip and shall be deemed to include a Channel Test.

1.2.3. Channel Check: A channel check is a qualitative verification of acceptable performance by observation of channel behavior, or by comparison of the channel with other independent channels or systems measuring the same variable.

1.2.4. Channel Test: A channel test is the introduction of a signal into the channel for verification that it is operable.

1.2.5. Cold Critical: The condition of the reactor when it is critical, with negligible xenon, and the fuel and bulk water are both at an isothermal temperature of 70'F.

1.2.6. Confinement

Confinement means a closure on the overall facility that controls the movement of air into and out of the facility through a controlled path.

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Appendix A Amendment 18 Technical Specifications 1.2.7. Control Rod: A control rod is a neutron absorbing blade having an in-line drive which is magnetically coupled and has SCRAM capability.

1.2.8. Excess Reactivity: Excess reactivity is that amount of reactivity that would exist if all control rods (and Shim Rod) were fully withdrawn from the point where the reactor is exactly critical (k1ff=l).

1.2.9. Experiment

Any operation, hardware, or target (excluding devices such as detectors, foils , etc.) that is designed to investigate non-routine reactor characteristics or that is intended for irradiation within the pool, on or in a beam tube or irradiation facility, and that is not rigidly secured to a core or shield structure so as to be a part of their design. Specific categories of experiments include:

a. Tried Experiment: Tried experiments are those experiments that have been previously performed in this reactor. Specifically, a tried experiment has similar size, shape, composition and location of an experiment previously approved and performed in the reactor.

b. Secured Experiment: A secured experiment is any experiment, experimental facility, or component of an experiment that is held in a stationary position relative to the reactor by mechanical means. The restraining forces must be substantially greater than those to which the experiment might be subjected by hydraulic, pneumatic, buoyant, or other forces which are normal to the operating environment of the experiment, or by forces which can arise as a result of credible malfunctions.

c. Non-Secured Experiment: A non-secured experiment is an experiment that does not meet the criteria for being a "secured" experiment.

d. Movable Experiment: A movable experiment is one where it is intended that all or part of the experiment may be moved in or near the core or into and out of the reactor while the reactor is operating.

e. Fueled Experiment: A fueled experiment is an experiment which contains fissionable material.

1.2.10. Experimental Facilities: Experimental facilities are facilities used to perform experiments. They include beam tubes, thermal columns, void tanks, pneumatic transfer systems, in-core facilities at single-assembly positions, out-of-core irradiation facilities, and the bulk irradiation facility.

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Appendix A Amendment 18 Technical Specifications 1.2.11. Limiting Condition for Operation: Limiting conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility (10CFR50.36).

1.2.12. Limiting Safety System Setting: Limiting safety system settings for nuclear reactors are settings for automatic protective devices related to those variables having significant safety functions. Where a limiting safety system setting is specified for a variable on which a safety limit has been placed, the setting must be so chosen that automatic protective action will correct the abnormal situation before a safety limit is exceeded (10CFR50.36).

1.2.13. Measured Value: The measured value is the value of a parameter as it appears on the output of a channel.

1.2.14. Operable: Operable means a component or system is capable of performing its intended function.

1.2.15. Operating: Operating means a component or system is performing its intended function.

1.2.16. pcm: A unit of reactivity that is the abbreviation for "percent millirho" and is equal to 10-5 Ak/k reactivity. For example, 1000 pcm is equal to 1.0% Ak/k.

1.2.17. Reactor Building: The Reactor Building includes the Reactor Bay, Control Room and Ventilation Room, the Mechanical Equipment Room (MER), and the Primary Piping Vault (PPV). The Nuclear Regulatory Commission R-120 license applies to the areas in the Reactor Building and the Waste Tank Vault.

1.2.18. Reactor Operation: Reactor operation is any condition when the reactor is not secured or shutdown.

1.2.19. Reactor Operator: A reactor operator (RO) is an individual who is licensed under 10 CFR 55 to manipulate the controls of the facility.

1.2.20. Reactor Operator Assistant (ROA): An individual who has been certified by successful completion of an in-house training program to assist the licensed reactor operator during reactor operation.

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Appendix A Amendment 18 Technical Specifications 1.2.21. Reactor Safety System: Reactor safety systems are those systems, including their associated input channels, which are designed to initiate automatic reactor protection or to provide information for initiation of manual protective action.

1.2.22. Reactor Secured: The reactor is secured when:

a. Either there is insufficient moderator available in the reactor to attain criticality or there is insufficient fissile material present in the reactor to attain criticality under optimum available conditions of moderation and reflection, or

b. The following conditions exist:

i. All scrammable neutron absorbing control rods are fully inserted, and ii. The reactor key switch is in the OFF position and the key is removed from the lock, and iii. No work is in progress involving core fuel, core structure, installed control rods, or control rod drives unless they are physically decoupled from the control rods, and iv. No experiments are being moved or serviced that have, on movement, a reactivity worth exceeding one dollar (730 pcm).

1.2.23. Reactor Shutdown: That subcritical condition of the reactor where the absolute value of the negative reactivity of the core is equal to or greater than the shutdown margin.

1.2.24. Reportable Event: A Reportable Event is any of the following:

a. Violation of a Safety Limit.

b. Release of radioactivity from the site above allowed limits.

c. Operation with actual Safety System Settings (SSS) for required systems less conservative than the Limiting Safety System Settings (LSSS) specified in these specifications.

d. Operation in violation of Limiting Conditions for Operation (LCO) established in these Technical Specifications.

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Appendix A Amendment 18 Technical Specifications

e. A reactor safety system component malfunction which renders or could render the reactor safety system incapable of performing its intended safety function unless the malfunction or condition is discovered during maintenance tests or periods of reactor shutdown.

(For components or systems other than those required by these Technical Specifications, the failure of the extra component or systems is not considered reportable provided that the minimum number of components or systems specified or required perform their intended reactor safety function).

f. An unanticipated or uncontrolled change in reactivity greater than one dollar (730 pcm). Reactor trips resulting from a known cause are excluded.

g. Abnormal or significant degradation in reactor fuel, or cladding, or both, coolant boundary, or confinement boundary (excluding minor leaks), which could result in exceeding radiological limits for personnel or environment, or both, as prescribed in the facility Emergency Plan.

h. An observed inadequacy in the implementation of administrative or procedural controls such that the inadequacy causes or could have caused the existence of an unsafe condition with regard to reactor operations.

1.2.25. Safety Limit: Safety limits for nuclear reactors are limits upon important process variables that are found to be necessary to reasonably protect the integrity of certain of the physical barriers that guard against the uncontrolled release of radioactivity (10CFR50.36).

1.2.26. Shim Rod: A shim rod is a neutron absorbing rod having an in-line drive which is mechanically, rather than magnetically, coupled and does not have a SCRAM capability.

1.2.27. Senior Reactor Operator: A senior reactor operator (SRO) is an individual who is licensed under 10 CFR 55 to manipulate the controls of the facility and to direct the activities of licensed reactor operators.

1.2.28. Shutdown Margin: Shutdown margin means the minimum shutdown reactivity necessary to provide confidence that the reactor can be made subcritical by means of the control and safety systems starting from any permissible operating condition with the most reactive scrammable rod fully withdrawn, the non-scrammable rod (Shim rod) fully withdrawn, and experiments considered at their most reactive condition, and finally, that the reactor will remain subcritical without further operator action.

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Appendix A Amendment 18 Technical Specifications 1.2.29. Total Nuclear Peaking Factor: The factor obtained by multiplying the measured local radial and axial neutron fluence peaking factors.

1.2.30. True Value: The true value is the actual value of a parameter.

1.2.31. University Management: University Management is the Chancellor or Office of the Chancellor other University Administrator(s) having authority designated by the Chancellor or as specified in University policies.

1.2.32 Unscheduled Shutdown: An unscheduled shutdown is defined as any unplanned shutdown of the reactor caused by actuation of the reactor safety system, operator error, equipment malfunction, or a manual shutdown in response to conditions that could adversely affect safe operation not including shutdowns that occur during testing or check-out operations.

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Appendix A Amendment 18 Technical Specifications 2.0. SAFETY LIMITS AND LIMITING SAFETY SYSTEM SETTINGS 2.1. Safety Limits (SL) 2.1.1. Safety Limits for Forced Convection Flow Applicability This specification applies to the interrelated variables associated with the core thermal and hydraulic performance with forced convection flow.

These interrelated variables are:

P Reactor Thermal Power W Reactor Coolant Flow Rate H Height of Water Above the Top of the Core Tinlet Reactor Coolant Inlet Temperature Obiective The objective is to assure that the integrity of the fuel clad is maintained.

Specification Under the condition of forced convection flow, the Safety Limit shall be as follows:

a. The combination of true values of reactor thermal power (P) and reactor coolant flow rate (W) shall not exceed the limits shown in Figure 2.1-1 under any operating conditions. The limits are considered exceeded if the point defined by the true values of P and W is at any time outside the operating envelope shown in Figure 2.1-1.

b. The true value of pool water level (H) shall not be less than 14 feet above the top of the core.

c. The true value of reactor coolant inlet temperature (Tiniet) shall not be greater than 120'F.

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Appendix A Amendment 18 Technical Specifications Bases Above 80 percent of the full core flow of 500 gpm in the region of full power operation, the criterion used to establish the Safety Limit was no bulk boiling at the outlet of any coolant channel. This was found to be far more limiting than the criterion of a minimum allowable burnout heat flux ratio of 2.0. The analysis is given in the SAR Appendix 3B.

In the region below 80 percent of full core flow, where, under a loss of flow transient at power the flow coasts down to zero, reverses, and then establishes natural convection, the criterion for selecting a Safety Limit is taken as a fuel cladding temperature. The analysis of a loss of flow transient is presented in Appendix 3B of the SAR. For initial conditions of full flow and an operating power of 1.4 MWt, the maximum clad temperature reached under the conservative assumptions of the analysis was 273°F which is well below the temperature at which fuel clad damage could possibly occur. The Safety Limit shown in Figure 2.1-1 for flow less than 80 percent of full flow is the steady state power corresponding to the maximum fuel clad temperature of 273°F with natural convection flow, namely, 1.4 MWt.

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Appendix A Amendment 18 Technical Specifications 5.0 4.5 4.0 Pool Level -14 feet Pool Temperature -120OF 3.5 3.0 0.

0 S2.0 0*

1.5 1.0 Operating Envelope 0.5 0.0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Fraction of Full Core Flow (500 gpm)

Figure 2.1-1: Power-Flow Safety Limit Curve 9

Appendix A Amendment 18 Technical Specifications 2.1.2. Safety Limits for Natural Convection Flow.

Applicability This specification applies to the interrelated variables associated with the core thermal and hydraulic performance with natural convection flow.

These interrelated variables are:

P Reactor Thermal Power H Height of Water Above the Top of the Core Tinlet Reactor Coolant Inlet Temperature Objective The objective is to assure that the integrity of the fuel clad is maintained.

Specification Under the condition of natural convection flow, the Safety Limit shall be as follows:

a. The true value of reactor thermal power (P) shall not exceed 1.4 MWt.

b. The true value of pool water level (H) shall not be less than 14 feet above the top of the core.

c. The true value of reactor coolant inlet temperature (Tiniet) shall not be greater than 120'F.

Bases The criterion for establishing a Safety Limit with natural convection flow is established as the fuel clad temperature. This is consistent with Figure 2.1-1 for forced convection flow during a transient. The analysis of natural convection flow given in Appendix 3B and 3C of the SAR shows that at 1.4 MWt the maximum fuel clad temperature is 273°F which is well below the temperature at which fuel clad damage could occur. The flow with natural convection at this power is 98 gpm. This flow is based on data from natural convection tests with fuel assemblies of the same design performed in the prototype PULSTAR Reactor, as referenced in Section 3 of the SAR.

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Appendix A Amendment 18 Technical Specifications 2.2. Limiting Safety System Settings 2.2.1. Limiting Safety System Settings (LSSS) for Forced Convection Flow Applicability This specification applies to the setpoints for the safety channels monitoring reactor thermal power (P), coolant flow rate (W), height of water above the top of the core (H), and pool water temperature (T).

Objective The objective is to assure that automatic protective action is initiated in order to prevent a Safety Limit from being exceeded.

Specification Under the condition of forced convection flow, the Limiting Safety System Settings shall be as follows:

P 1.3 MWt (max.)

W 450 gpm (min.)

H 14 feet, 2 inches (min.)

T 117 0 F Bases The Limiting Safety System Settings that are given in the Specification 2.2.1 represent values of the interrelated variables which, if exceeded, shall result in automatic protective actions that will prevent Safety Limits from being exceeded during the most limiting anticipated transient (loss of flow). The safety margin that is provided between the Limiting Safety System Settings and the Safety Limits also allows for the most adverse combination of instrument uncertainties associated with measuring the observable parameters. These instrument uncertainties include a flow variation of ten percent, a pool level variation of two inches and a power level variation of seven percent.

The analysis presented in Section 3 of the SAR of a loss of flow transient indicates that if the interrelated variables were at their LSSS, as specified in 2.2.1 above, at the initiation of the transient, the Safety Limits specified in 2.1.1 would not be exceeded.

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Appendix A Amendment 18 Technical Specifications 2.2.2. Limiting Safety System Settings (LSSS) for Natural Convection Flow Applicability This specification applies to the setpoints for the safety channel monitoring reactor thermal power (P), the height of water above the core (H), and the pool water temperature (T).

Objective The objective is to assure that automatic protective action is initiated in order to prevent a Safety Limit from being exceeded.

Specifications Under the condition of natural convection flow, the Limiting Safety System Settings shall be as follows:

P 250 kWt (max.)

H 14 feet, 2 inches (min.)

T 117 0 F Bases The Limiting Safety System Settings that are given in Specification 2.2.2 represent values of the interrelated variables which, if exceeded, shall result in automatic protective actions that will prevent Safety Limits from being exceeded. The specifications given above assure that an adequate safety margin exists between the LSSS and the SL for natural convection.

The safety margin on reactor thermal power was chosen with the additional consideration related to bulk boiling at the outlet of the hot channel. This criterion is not related to fuel clad damage (for these relatively low power levels) which was the criterion used in establishing the Safety Limits (see Specification 2.1.2). It is desirable to minimize to the greatest extent practical, N- 16 dose at the pool surface which might be aided by steam bubble rise during up-flow in natural convection. Analysis of coolant bulk boiling given in SAR, Section 3, indicates that the large safety margin on reactor thermal power assumed in Specification 2.2.2 above will satisfy this additional criterion of no bulk boiling in any channel.

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Appendix A Amendment 18 Technical Specifications 3.0. LIMITING CONDITIONS FOR OPERATION 3.1. Reactor Core Configuration Applicability This specification applies to the reactor core configuration during forced convection or natural convection flow operations.

Objective The objective is to assure that the reactor will be operated within the bounds of established Safety Limits.

Specification The reactor shall not be operated unless the following conditions exist:

a. A maximum of twenty-five fuel assemblies.

b. A maximum of ten reflector assemblies of either graphite or beryllium or a combination of these located on the core periphery.

c. Unoccupied grid plate penetrations plugged.

d. A minimum of four control rod guides are in place.

e. The maximum worth of a single fuel assembly shall not exceed 1590 pcm.

f. The total nuclear peaking factor in any fuel assembly shall not exceed 2.92.

Bases Specifications 3.1 .a through 3.1 .d require that the core be configured such that there is no bypass cooling flow around the fuel through the grid plate.

Specification 3.1 .e provides assurances that a fuel loading accident will not result in a Safety Limit to be exceeded as discussed in SAR Section 13.2.2.1.

Specification 3.1 .f provides assurances that core hot channel power are bounded by the SAR assumptions in Appendix 3-B.

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Appendix A Amendment 18 Technical Specifications 3.2. Reactivity Applicability This specification applies to the reactivity condition of the reactor and the reactivity worths of control rods, shim rod and experiments.

Objective The objective is to assure that the reactor can be shutdown at all times and that the Safety Limits will not be exceeded.

Specifications The reactor shall not be operated unless the following conditions exist:

a. The shutdown margin, with the highest worth scrammable control rod fully withdrawn, with the shim rod fully withdrawn, and with experiments at their most reactive condition, relative to the cold critical condition, is greater than 400 pcm.

b. The excess reactivity is not greater than 3970 pcm.

c. The drop time of each control rod is not greater than 1.0 second.

d. The rate of reactivity insertion of the control rods is not greater than 100 pcm per second (critical region only).

e. The absolute reactivity worth of experiments or their rate of reactivity change shall not exceed the values indicated in Table 3.2-1.

f. The sum of the absolute values of the reactivity worths of all experiments shall not be greater than 2890 pcm.

Table 3.2-1: Reactivity Limits for Experiments Experiment Limit 300 pcm or 100 pcm/sec, whichever is more Movable lmtn limiting Non-secured 1000 pcm Secured 1590 pcm 14

Appendix A Amendment 18 Technical Specifications Bases The shutdown margin required by Specification 3.2.a assures that the reactor can be shut down from any operating condition and will remain shutdown after cool down and xenon decay, even if the highest worth scrammable rod should be in the fully withdrawn position. Refer to Section 3.1.2.1.

The upper limit on excess reactivity ensures that an adequate shutdown margin is maintained.

The rod drop time required by Specification 3.2.c assures that the Safety Limit will not be exceeded during the flow reversal which occurs upon loss of forced convection coolant flow. The rise in fuel temperature due to heat storage is partially controlled by the reactivity insertion associated with the SCRAM. The analysis of this transient is based upon this SCRAM reactivity insertion taking the form of a ramp function of two second duration. This analysis is found in SAR Section 3.2.4 and Appendix 3B. The rod drop time is the time interval measured between the instant of a test signal input to the SCRAM Logic Unit and the instant of the rod seated signal.

The maximum rate of reactivity insertion by the control rods which is allowed by Specification 3.2.d assures that the Safety Limit will not be exceeded during a startup accident due to a continuous linear reactivity insertion. Refer to SAR Section 13.

Experiments affecting the reactivity condition of the reactor are commonly categorized by the sign of the reactivity effect produced by insertion of the experiment. An experiment having a large reactivity effect of either sign can also produce an undesirable flux distribution that could affect the peaking factor used in the Safety Limit calculations and the calibration of Safety Channels.

The Specification 3.2.e is intended to prevent inadvertent reactivity changes during reactor operation caused by the insertion or removal of an experiment. It further provides assurance that the failure of a single experiment will not result in a reactivity insertion which could cause the Safety Limit to be exceeded.

Analyses indicate that the inadvertent reactivity insertion of these magnitudes will not result in consequences greater than those analyzed in the SAR Sections 3 and 13.

The total limit on reactivity associated with experiments ensures that an adequate shutdown margin is maintained.

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Appendix A Amendment 18 Technical Specifications 3.3. Reactor Safety System Applicability This specification applies to the reactor safety system channels.

Objective The objective is to require the minimum number of reactor safety system channels which must be operable in order to assure that the Safety Limits are not exceeded.

Specification The reactor shall not be operated unless the reactor safety system channels described in Table 3.3-1 are operable.

Table 3.3-1: Required Safety and Safety Related Channels Measuring Channel Function

a. Startup Power Level(') Inhibits Control Rod withdrawal when neutron count is *2 cps SCRAM at <1.3 MW (LSSS)

b. Safety Power Level Enable for Flow/Flapper SCRAMs at

_<250 kW (LSSS)

c. Linear Power Level SCRAM at *<1.3 MW (LSSS)

Enable for Flow/Flapper SCRAMs at

d. Log N Power Level *5 kW

_<250 W(SS (LSSS)

e. Flow Monitoring (2) SCRAM when flapper not closed and Flow/Flapper SCRAMs are enabled

f. Primary Coolant Flow(2) SCRAM at >450 gpm (LSSS) when Flow/Flapper SCRAMs are enabled Pool Water Temperature ALARM at:5117 0 F

g. Monitoring Switch

h. Pool Water Temperature Measuring SCRAM at_<117 0 F (LSSS)

Channel

i. Pool Water Level SCRAM at _>14 feet 2 inches

j. Manual SCRAM Button SCRAM

k. Reactor Key Switch SCRAM

1. Over-the-Pool Radiation Monitor(') Alarm (100 mR/hr) 16

Appendix A Amendment 18 Technical Specifications

() Required only for reactor startup when power level is less than 4 watts.

(2) Either the Flapper SCRAM or the Flow SCRAM may be bypassed during maintenance testing and/or performance of a startup checklist in order to verify each SCRAM is independently operable. The reactor must be shutdown in order to use these bypasses.

(3) May be bypassed for less than two minutes during the return of a pneumatic capsule from the core to the unloading station or five minutes during removal of experiments from the reactor pool. Refer to SAR Section 5.

Bases The Startup Channel inhibit function assures the required startup neutron source is sufficient and in its proper location for the reactor startup, such that a minimum source multiplication count rate level is being detected to assure adequate information is available to the operator.

The reactor power level SCRAMs provide the redundant protection channels to assure that, if a condition should develop which would tend to cause the reactor to operate at an abnormally high power level, an immediate automatic protective action will occur to prevent exceeding the Safety Limit.

The primary coolant flow SCRAMs provide redundant channels to assure when the reactor is at power levels which require forced flow cooling that, if sufficient flow is not present, an immediate automatic shutdown of the reactor will occur to prevent exceeding a Safety Limit. The Log N Power Channel is included in this section since it is one of the two channels which enables the two flow SCRAMs when the reactor is above 250 kW (LSSS).

The pool water temperature channel provides for shutdown of the reactor and prevents exceeding the Safety Limit due to high pool water temperature.

The pool water level channel together with the Over-the-Pool (Bridge) radiation monitor, provides two diverse channels for shutdown of the reactor and prevents exceeding the Safety Limit due to insufficient pool height.

To prevent unnecessary initiation of the evacuation and confinement systems during the return of the pneumatic capsule from the core to the unloading station or during the removal of experiments from the reactor pool, the Over-the-Pool monitor may be bypassed for the specified time interval.

The manual SCRAM button and the Reactor Key switch provide two manual SCRAM methods to the reactor operator if unsafe or abnormal conditions should occur.

17

Appendix A Amendment 18 Technical Specifications 3.4. Reactor Instrumentation Applicability This specification applies to the instrumentation that shall be available to the reactor operator to support the safe operation of the reactor, but are not considered reactor safety systems.

Objective The objective is to require that sufficient information be available to the operator to assure safe operation of the reactor.

Specification The reactor shall not be operated unless the following are operable:

a. N-16 Power Measuring Channel when reactor power is greater than 500 kW

b. Control Rod Position Indications for each control rod and the Shim Rod

c. Differential pressure gauge for "Bay with Respect to Atmosphere" Bases The N-16 Channel provides the necessary power level information to allow adjustment of Safety and Linear Power Channels.

Control rod position indications give the operator information on rod height necessary to verify shutdown margin.

The differential pressure gauge provides the pressure difference between the Reactor Bay and the outside ambient and confirms air flow in the ventilation stream for both normal and confinement modes.

18

Appendix A Amendment 18 Technical Specifications 3.5. Radiation Monitoring Equipment Applicability This specification applies to the availability of radiation monitoring equipment which must be operable during reactor operation.

Objective To assure that radiation monitoring equipment is available for evaluation of radiation conditions in restricted and unrestricted areas.

Specification The reactor shall not be operated unless the radiation monitoring equipment listed in Table 3.5-1 is operable. (1)(2)(3)

a. Three fixed area monitors operating in the Reactor Building with their setpoints as listed in Table 3.5-1.

b. Particulate and gas building exhaust monitors continuously sampling air in the

.facility exhaust stack with their setpoints as listed in Table 3.5-1 .(1)(3)(4)

c. The Radiation Rack Recorder.(5)

Table 3.5-1: Required Radiation Area Monitors Monitor Alert Setpoint Alarm Setpoint Control Room < 2 mR/hr < 5 mR/hr Over-the-Pool < 5 mR/hr < 100 mR/hr West Wall < 5 mR/hr _<100 mR/hr Stack Gas < 1000 Ar-41 AEC&6 ) < 5,000 Ar-41AEC(6)

Stack Particulate _<1000 Co-60 AEC(6) -<5,000 Co-60 AEC(6) 19

Appendix A Amendment 18 Technical Specifications (1)For periods of time, not to exceed ninety days, for maintenance to the radiation monitoring channel, the intent of this specification will be satisfied if one of the installed channels is replaced with a gamma-sensitive instrument which has its own alarm audible or observable in the control room. Refer to SAR Section 5.

(2) The Over-the-Pool Monitor may be bypassed for less than two minutes during return of a pneumatic capsule from the core to the unloading station or five minutes during removal of experiments from the reactor pool. Refer to SAR Section 5.

(3) Stack Gas and Particulate are based on the AEC quantities present in the ventilation flow stream as it exits the stack. Refer to SAR Section 10 for setpoint bases for the radiation monitoring equipment.

(4) May be bypassed for less than one minute immediately after starting the pneumatic blower system.

(5) During repair and/or maintenance of the recorder not to exceed 90 days, the specified area and effluent monitor readings shall be recorded manually at a nominal interval of 30 minutes when the reactor is not shutdown. Refer to SAR Section 5.

(6) Airborne Effluent Concentrations (AEC) values from IOCFR20 Appendix B, Table 2 Bases A continued evaluation of the radiation levels within the Reactor Building will be made to assure the safety of personnel. This is accomplished by the area monitoring system of the type described in Section 5 of the SAR.

Evaluation of the continued discharge air to the environment will be made using the information recorded from the particulate and gas monitors.

When the radiation levels reach the alarm setpoint on any single area, or stack exhaust monitor, the building will be automatically placed in confinement as described in SAR Section 5.

To prevent unnecessary initiation of the evacuation confinement system during the return of a pneumatic capsule from the core to the unloading station or during removal of experiments from the reactor pool, the Over-the-Pool Monitor may be bypassed during the specified time interval. Refer to SAR Section 5.

20

Appendix A. Amendment 18 Technical Specifications 3.6. Confinement and Main HVAC Systems Applicability This specification applies to the operation of the Reactor Building confinement and main HVAC systems.

Objective The objective is to assure that the confinement system is in operation to mitigate the consequences of possible release of radioactive materials resulting from reactor operation.

Specification The reactor shall not be operated, nor shall irradiated fuel be moved within the pool area, unless the following equipment is operable, and conditions met:

Table 3.6-1: Required Main HVAC and Confinement Conditions Equipment/Condition Function

a. All doors, except the Control To maintain reactor building Room, and basement corridor negative differential pressure (dp).(')

entrance: self-latching, self-closing, closed and locked.

b. Control room and basement To maintain reactor building corridor entrance door: self- negative differential pressure.(2) latching, self-closing and closed.

c. Reactor Building under a negative To maintain reactor building differential pressure of not less than negative differential pressure with 0.2" H 2 0 with the normal reference to outside ambient.()

ventilation system or 0.1" H 2 0 with one confinement fan operating.

d. Confinement system Operable(4)5)(7)

e. Evacuation system Operable(6)

(')Doors may be opened by authorized personnel for less than five minutes for personnel and equipment transport provided audible and visual indications are available for the reactor operator to verify door status. Refer to SAR Section 5.

(2) Doors may be opened for periods of less than five minutes for personnel and equipment transport between corridor area and Reactor Building. Refer to SAR Section 5.

21

Appendix A Amendment 18 Technical Specifications (3) During an interval not to exceed 30 minutes after a loss of dp is identified with Main HVAC operating, reactor operation may continue while the loss of dp is investigated and corrected. Refer to SAR Section 5.

(4) Operability also demonstrated with an auxiliary power source.

(5) One filter train may be out of service for the purpose of maintenance, repair, and/or surveillance for a period of time not to exceed 45 days. During the period of time in which one filter train is out of service, the standby filter train shall be verified to be operable every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> if the reactor is operating with the Reactor Building in normal ventilation.

(6) The public address system can serve temporarily for the Reactor Building evacuation system during short periods of maintenance.

(7) When the radiation levels reach the alarm setpoint on any single area, or stack exhaust monitor, listed in Table 3.5-1 , the building will be automatically placed in confinement as described in SAR Section 5.

Bases In the event of a fission product release, the confinement initiation system will secure the normal ventilation fans and close the normal inlet and exhaust dampers.

In confinement mode, a confinement system fan will: maintain a negative pressure in the Reactor Building and insure in-leakage only; purge the air from the building at a greatly reduced and controlled flow through charcoal and absolute filters; and control the discharge of all air through a 100 foot stack on site.

Section 5 of the SAR describes the confinement system sequence of operation.

The allowance for operation under a temporary loss of dp when in normal ventilation is based on the requirement of having the confinement system operable and therefore ready to respond in the unlikely event of an airborne release.

22

Appendix A Amendment 18 Technical Specifications 3.7. Limitations of Experiments Applicability This specification applies to experiments installed in the reactor and its experimental facilities. Fueled experiments must also meet the requirements of Specification 3.8.

Objective The objective is to prevent damage to the reactor or excessive release of radioactive materials in the event of an experiment failure.

Specification The reactor shall not be operated unless the following conditions governing experiments exist:

a. All materials to be irradiated shall be either corrosion resistant or encapsulated within a corrosion resistant container to prevent interaction with reactor components or pool water. Corrosive materials, liquids, and gases shall be doubly encapsulated.

b. Irradiation containers to be used in the reactor, in which a static pressure will exist or in which a pressure buildup is predicted, shall be designed and tested for a pressure exceeding the maximum expected by a factor of 2. Pressure buildup inside any container shall be limited to 200 psi.

c. Cooling shall be provided to prevent the surface temperature of an experiment to be irradiated from exceeding the saturation temperature of the reactor pool water.

d. Experimental apparatus, material or equipment to be inserted in the reactor shall be positioned so as to not cause shadowing of the nuclear instrumentation, interference with control rods, or other perturbations which may interfere with safe operation of the reactor.

e. Concerning the material content of experiments, the following will apply:

i. No experiment will be performed unless the major constituent of the material to be irradiated is known and a reasonable effort has been made to identify trace elements and impurities whose activation may pose the dominant radiological hazard. When a reasonable effort does not give conclusive information, one or more short irradiations of small quantities of material may be performed in order to identify the activated products.

23

Appendix A Amendment 18 Technical Specifications ii. Attempts will be made to identify and limit the quantities of elements having very large thermal neutron absorption cross sections, in order to quantify reactivity effects.

iii. Explosive material(') shall not be allowed in the reactor. Experiments in which the material is considered to be potentially explosive, either while contained, or if it leaks from the container, shall be designed to maintain seal integrity even if detonated, to prevent damage to the reactor core or to the control rods or instrumentation and to prevent any change in reactivity.

iv. Each experiment will be evaluated with respect to radiation induced physical and/or chemical changes in the irradiated material, such as decomposition effects in polymers.

v. Experiments involving cryogenic liquids(l) within the biological shield, flammable('), or highly toxic materials(') require specific procedures for handling and shall be limited in quantity and approved as specified in Specification 6.2.3.

f. Credible failure of any experiment shall not result in releases or exposures in excess of the annual limits established in 10CFR20.

(1)Defined as follows (reference - Handbook of LaboratorySafety - Chemical Rubber Company, 4 th Ed., 1995, unless otherwise noted):

Toxic: A substance that has the ability to cause damage to living tissue when inhaled, ingested, injected, or absorbed through the skin (Safety in Academic Chemistry Laboratories- The American Chemical Society, 1994).

Flammable: Having a flash point below 73°F and a boiling point below 100°F. The flash point is defined as the minimum temperature at which a liquid forms a vapor above its surface in sufficient concentrations that it may be ignited as determined by appropriate test procedures and apparatus as specified.

Explosive: Any chemical compound, mixture, or device, where the primary or common purpose of which is to function by explosion with substantially simultaneous release of gas and heat, the resultant pressure being capable of destructive effects. The term includes, but is not limited to, dynamite, black powder, pellet powder, initiating explosives, detonators, safety fuses, squibs, detonating cord, igniter cord, and igniters.

Cryogenic: A cryogenic liquid is considered to be a liquid with a normal boiling point below -238°F (reference - National Bureau of Standards Handbook 44).

24

Appendix A Amendment 18 Technical Specifications Bases Specifications 3.7.a, 3.7.b, 3.7.c, and 3.7.d are intended to reduce the likelihood of damage to reactor components and/or radioactivity releases resulting from experiment failure; and, serve as a guide for the review and approval of new and untried experiments.

Specification 3.7.e ensures that no physical or nuclear interferences compromise the safe operation of the reactor, specifically, an experiment having a large reactivity effect of either sign could produce an undesirable flux distribution that could affect the peaking factor used in the Safety Limit calculation and/or safety channels calibrations. Review of experiments using the specifications of Section 3 and Section 6 will ensure the insertion of experiments will not negate the considerations implicit in the Safety Limits and thereby violate license conditions.

25

Appendix A Amendment 18 Technical Specifications 3.8. Operations with Fueled Experiments Applicability This specification applies to the operation of the reactor with any fueled experiment.

Objective The objective is to prevent damage to the reactor or excessive release of radioactive materials in the event of an experiment failure.

Specifications Fueled experiments may be performed in experimental facilities of the reactor with the following conditions and limitations:

a. The fission rate is limited as follows:

i. Figure 3.8-1 and Table 3.8-1 for isotopes of uranium (U) and plutonium (Pu) ii. Figure 3.8-2 and Table 3.8-2 for all other fissionable materials

b. The reactor shall not be operated with a fueled experiment unless the ventilation system is operated in the confinement mode.

c. Specification 3.2 pertaining to reactivity shall be met.

d. Specification 3.7 pertaining to reactor experiments shall be met.

e. Specification 6.5 pertaining to the review of experiments shall be met.

Each type of fueled experiment shall be classified as a new (untried) experiment with a documented review. The documented review shall include the following items:

i. Meeting license requirements for the receipt, use, and storage of fissionable material.

ii. Limiting the thermal power generated from the fissile material to ensure that the surface temperature of the experiment does not exceed the saturation temperature of the reactor pool water.

iii. Radiation monitoring for detection of released fission products.

26

Appendix A Amendment 18 Technical Specifications iv. Design criteria related to meeting conditions given in Specifications 3.2 and 3.7.

v. Sample is irradiated and unloaded within the reactor building

f. Credible failure of any fueled experiment shall not result in releases or exposures in excess of 10% of the annual limits established in 10CFR20.

1.00E+12 N Allowed Fission Rate 1.00E+t1 1.00E÷09 1.00E-08 1.00E+07 1.0OE+06 1.00E-03 1.OOE+01 3.OOE+01 1.OOE+02 3.OOE+02 1.00E+03 3.OOE+03 1.OOE+04 300E+04 1.00E+05 3.OOE+05 I.DOE+06 3.OOE+06 1.OOE+07 3,OOE+07 3.15E+07 Irradlfoni Time(a)

Figure 3.8-1: Fueled Experiment Limiting Fission Rates for Isotopes of U or Pu()(2)

(')The fission rate at 10 seconds applies to irradiation times up to 10 seconds.

(2)Irradiation time is limited to 3.15 E7 seconds (1 year).

27

Appendix A Amendment 18 Technical Specifications Table 3.8-1: Limiting Fission Rates for Isotopes of U and Pu Irradiation time (s) U and Pu Fission Rate (f/s) 1.00E-03 2.67E+11 1.OOE+O1 2.67E+11 3.OOE+01 9.94E+10 1.OOE+02 4.10E+10 3.OOE+02 1.97E+10 1.00E+03 9.18E+09 3.OOE+03 4.73E+09 1.00E+04 2.43E+09 3.OOE+04 1.43E+09 1.00E+05 9.14E+08 3.OOE+05 6.88E+08 1.00E+06 5.67E+08 3.OOE+06 5.13E+08 1.00E+07 4.81E+08 3.OOE+07 4.65E+08 3.15E+07 4.65E+08 where, (f/s) = 4.7E12[t-' 7] + 7.7E1 1[t-° 65] + 5.4E8[t-°'0 ]

(f/s) is the limiting fission rate for irradiation time "t" "t" is in seconds and is limited to 3.15 E7 s (1 year)

The fission rate at 10 seconds applies to irradiation times less than 10 seconds 28

Appendix A Amendment 18 Technical Specifications 1.00E+12 1,00E+10 1.OOE+08.

I.O0E+07 1.00E+06 I.OOE-03 1.00E+01 3.OOE+011.00E+02 3.OOE+021.OOE+033.OOE+031.O0E+04 3.OOE+04 1.00E+05 3.OOE+051.00E+06 3.00E406 1,00E+07 3OOE+07 3,15E+07 IrrdiacUOr Time (s)

Figure 3.8-2: Fueled Experiment Limiting Fission Rates for All Other Fissionable Materials ()(2)

(')The fission rate at 10 seconds applies to irradiation times up to 10 seconds.

(2)Irradiation time is limited to 3.15 E7 seconds (1 year).

29

Appendix A Amendment 18 Technical Specifications Table 3.8-2: Limiting Fission Rates for All Other Fissionable Materials Irradiation time (s) All Other Materials Fission Rate (f/s) 1.00E-03 2.66E+11 1.00E+01 2.66E+ 11 3.OOE+01 9.07E+10 1.00E+02 2.79E+10 3.OOE+02 9.56E+09 1.00E+03 2.99E+09 3.OOE+03 1.06E+09 1.00E+04 3.74E+08 3.OOE+04 1.72E+08 1.00E+05 9.93E+07 3.OOE+05 7.74E+07 1.00E+06 6.91E+07 3.OOE+06 6.62E+07 1.00E+07 6.46E+07 3.OOE+07 6.37E+07 3.15E+07 6.36E+07 where, (f / s) = 2.54E1 2[t- 98 ] +7.55E7[t- 0° 1]

(f/s) is the limiting fission rate for irradiation time "t" "t" is in seconds and is limited to 3.15 E7 s (1 year)

The fission rate at 10 seconds applies to irradiation times less than 10 seconds Bases NUREG 1537 provides guidelines for the format and content of non-power reactor licensing. Guidelines on operating conditions and accident analysis for fueled experiments are given in NUREG 1537. These guidelines include (1) actuation of engineered safety features (ESF) to prevent or mitigate the consequences of damage to fission product barriers caused by overpower or loss of cooling events, (2) use of ESF to control of radioactive material released by accidents, (3) radiation monitoring of fission product effluent and accident releases, (4) accident analysis for loss of cooling or other experimental malfunction resulting in liquefaction or volatilization of fissile materials, (5) accident analysis for catastrophic failure of the experiment in the reactor pool or air, 30

Appendix A Amendment 18 Technical Specifications (6) accident analysis for insertion of excess reactivity leading to fuel melting, and (7) emergency plan activation and classification The limitations given in Specification 3.8 ensure that (1) fueled experiments performed in experimental facilities at the reactor prevent damage to the reactor or excessive release of radioactive materials in the event of an experiment failure, (2) radiation doses to occupational personnel and the public and radioactive material releases are ALARA, (3) adequate radiation monitoring is in place, and (4) in the event of failure of a fueled experiment with the subsequent release of radioactive material, the resulting dose to personnel and the public at any location are well within limits set in 10 CFR 20.

Specification 3.8 e ensures that each type of fueled experiment is reviewed, approved, and documented as required by Specification 6.5. This includes (1) meeting applicable limitations on experiments given in Specifications 3.2 and 3.7, (2) limiting the amount of fissile material to ensure that experimental reactivity conditions are met and that radiation doses are well within 10 CFR 20 limits following maximum fission product release from a failed experiment, and (3) limiting the thermal power generated from the fissile material to ensure that the surface temperature of the experiment does not exceed the saturation temperature of the reactor pool water.

31

Appendix A Amendment 18 Technical Specifications 3.9. Primary Coolant Applicability This specification applies to the water quality and flow path of the primary coolant.

Objective The objective is to ensure that primary coolant quality be maintained to acceptable values in order to reduce the potential for corrosion and limit the buildup of activated contaminants in the primary piping and pool.

Specification The reactor shall not be operated unless the pool water meets the following limits:

a. The resistivity shall be _Ž500 kM.cm.

b. The pH shall be within the range of 5.5 to 7.5.

Bases The limits on resistivity are based on reducing the potential for corrosion in the primary piping or pool liner and to reduce the potential for activated contaminants in these systems.

32

Appendix A Amendment 18 Technical Specifications 4.0. SURVEILLANCE REQUIREMENTS All surveillance tests required by these specifications are scheduled as described; however, some system tests may be postponed at the required intervals if that system or a closely associated system is undergoing maintenance. Any pending surveillance tests will be completed prior to reactor startup. Any surveillance item(s) which require reactor operation will be completed immediately after reactor startup. Surveillance requirements scheduled to occur during extended operation which cannot be performed while the reactor is operating may be deferred until the next planned reactor shutdown.

The intent of the surveillance interval (e.g., annually, but not to exceed fifteen months) is to maintain an average cycle, with occasional extensions as allowed by the interval tolerance. If it is desired to permanently change the scheduled date of surveillance, the particular surveillance item will be performed at an earlier date and the associated interval normalized to this revised earlier date. In no cases will permanent scheduling changes, which yield slippage of the surveillance interval routine scheduled date, be made by using the allowed interval tolerance.

4.1. Fuel Applicability This specification applies to the surveillance requirement for the reactor fuel.

Objective The objective is to monitor the physical condition of the PULSTAR fuel.

Specification

a. All fuel assemblies shall be visually inspected for physical damage biennially but at intervals not to exceed thirty (30) months.

b. The reactor will be operated at such power levels necessary to determine if an assembly has had fuel pin cladding failure.

Bases Each fuel assembly is visually inspected for physical damage that would include corrosion of the end fitting, end box, zircaloy box, missing fasteners, dents, severe surface scratches,'and blocked coolant channels.

Based on a long history of prototype PULSTAR operation in conjunction with primary coolant analysis, biennial inspections of PULSTAR fuel to ensure fuel assembly integrity have been shown to be adequate for Zircoloy-2 (Zr-2) clad fuel. Any assembly that appears to have leaking fuel pin(s) will be disassembled 33

Appendix A Amendment 18 Technical Specifications to confirm and isolate damaged fuel pins. Damaged fuel pins will be logged as such and permanently removed from service.

4.2. Control Rods Applicability This specification applies to the surveillance requirements for the control rods, shim rod, and control rod drive mechanisms (CRDM).

Objective The objective is to assure the operability of the control rods and shim rod, and to provide current reactivity data for use in verifying adequate shutdown margin.

Specification

a. The reactivity worth of the shim rod and each control rod shall be determined annually but at intervals not to exceed fifteen (15) months for the steady state core in current use. The reactivity worth of all rods shall be determined for any new core or rod configuration, prior to routine operation.

b. Control rod drop times(l) and control rod drive times shall be determined:

i. Annually but at intervals not to exceed fifteen (15) months.

ii. After a control assembly is moved to a new position in the core or after maintenance or modification is performed on the control rod drive mechanism.

c. The control rods shall be visually inspected biennially but at intervals not to exceed thirty (30) months.

d. The values of excess reactivity and shutdown margin shall be determined monthly, but at intervals not to exceed six (6) weeks, and for new core configurations.

) Applies only to magnetically coupled rods.

34

Appendix A Amendment 18 Technical Specifications Bases The reactivity worth of the control rods is measured to assure that the required shutdown margin is available and to provide a means for determining the reactivity worths of experiments inserted in the core. The measurement of reactivity worths on an annual basis provides a correction for the slight variations expected due to bumup. This frequency of measurement has been found acceptable at similar research reactor facilities, particularly the prototype PULSTAR which has a similar slow change of rod value with bum-up.

Control rod drive and drop time measurements are made to determine whether the rods are functionally operable. These time measurements may also be utilized in reactor transient analysis.

Visual inspections include: detection of wear or corrosion in the rod drive mechanism; identification of deterioration, corrosion, flaking or bowing of the neutron absorber material; and verification of rod travel setpoints.

Control rod surveillance procedures will document proper control rod system reassembly after maintenance and recorded post-maintenance data will identify significant trends in rod performance.

35

Appendix A Amendment 18 Technical Specifications 4.3. Reactor Instrumentation and Safety Systems Applicability This specification applies to the surveillance requirements for the Reactor Safety System and other required reactor instruments.

Objective The objective is to assure that the required instrumentation and Safety Systems will remain operable and will prevent the Safety Limits from being exceeded.

Specification

a. A channel check of each measuring channel in the RSS shall be performed daily when the reactor is in operation.

b. A channel test of each channel in the RSS shall be performed prior to operation each day, or prior to each operation extending more than one day.

c. A channel calibration of the N- 16 Channel shall be made semi-annually, but at intervals not to exceed seven and one-half (7!/2) months. A calorimetric measurement shall be performed to determine the N-16 detector current associated with full power operation.

d. A channel calibration of the following channels shall be made semi-annually but at intervals not to exceed seven and one-half (71/2/2) months.0)

i. Pool Water Temperature ii. Primary Cooling and Flow Monitoring (Flapper) iii. Pool Water Level iv. Primary Heat Exchanger Inlet and Outlet Temperature

v. Safety and Linear Power Channels

() A channel calibration shall also be required after repair of a channel component that has the potential of affecting the calibration of the channel.

Bases The daily channel tests and checks will assure the Reactor Safety Systems are operable and will assure operations within the limits of the operating license. The semi-annual calibrations will assure that long term drift of the channels is corrected. The calorimetric calibration of the reactor power level, in conjunction with the N-16 Channel, provides a continual reference for adjustment of the Linear, Log N and Safety Channel detector positions.

36

Appendix A Amendment 18 Technical Specifications 4.4. Radiation Monitoring Equipment Applicability This specification applies to the surveillance requirements for the area and stack effluent radiation monitoring equipment.

Objective The objective is to assure that the radiation monitoring equipment is operable.

Specification

a. The area and stack monitoring systems shall be calibrated annually but at intervals not to exceed fifteen (15) months.

b. The setpoints shall be verified weekly, but at intervals not to exceed ten (10) days.

Bases These systems provide continuous radiation monitoring of the Reactor Building with a check of readings performed prior to and during reactor operations.

Therefore, the weekly verification of the setpoints in conjunction with the annual calibration is adequate to identify long term variations in the system operating characteristics.

37

Appendix A Amendment 18 Technical Specifications 4.5. Confinement and Main HVAC System Applicability This specification applies to the surveillance requirements for the confinement and main HVAC systems.

Objective The objective is to assure that the confinement system is operable.

Specification

a. The confinement and evacuation system shall be verified to be operable within seven (7) days prior to reactor operation.

b. Operability of the confinement system on auxiliary power will be checked monthly but at intervals not to exceed six (6) weeks.0)

c. A visual inspection of the door seals and closures, dampers and gaskets of the confinement and ventilation systems shall be performed semi-annually but at intervals not to exceed seven and one-half (7V2) months toverify they are operable.

d. The control room differential pressure (dp) gauges shall be calibrated annually but at intervals not to exceed fifteen (15) months.

e. The confinement filter train shall be tested biennially but at intervals not to exceed thirty (30) months and prior to reactor operation following confinement HEPA or carbon adsorber replacement. This testing shall include iodine adsorption, particulate removal efficiency and leak testing of the filter housing.(2)

f. The air flow rate in the confinement stack exhaust duct shall be determined annually but at intervals not to exceed fifteen (15) months. The air flow shall be not less than 600 CFM.

(1) Operation must be verified following modifications or repairs involving load changes to the auxiliary power source.

(2) Testing shall also be required following major maintenance of the filters or housing.

Bases Surveillance of this equipment will verify that the confinement of the Reactor Building is maintained as described in Section 5 of the SAR.

38

Appendix A Amendment 18 Technical Specifications 4.6. Primary and Secondary Coolant Applicability This specification applies to the surveillance requirement for monitoring the radioactivity in the primary and secondary coolant.

Objective The objective is to monitor the radioactivity in the pool water to verify the.

integrity of the fuel cladding and other reactor structural components. The secondary water analysis is used to confirm the boundary integrity of the primary heat exchanger.

Specification

a. The primary coolant shall be analyzed bi-weekly, but at intervals not to exceed eighteen (18) days. The analysis shall include gross beta/gamma counting of the dried residue of a one (1) liter sample or gamma spectroscopy of a liquid sample, neutron activation analysis (NAA) of an aliquot, and pH and resistivity measurements.

b. The secondary coolant shall be analyzed bi-weekly, but at intervals not to exceed eighteen (18) days. This analysis shall include gross beta/gamma counting of the dried residue of a one (1) liter sample or gamma spectroscopy of a liquid sample.

Bases Radionuclide analysis of the pool water samples will allow detection of fuel clad failure, while neutron activation analysis will give corrosion data associated with primary system components in contact with the coolant. Refer to SAR Section 10.

The detection of activation or fission products in the secondary coolant provides evidence of a primary heat exchanger leak. Refer to SAR Section 10.

39

Appendix A Amendment 18 Technical Specifications 5.0. DESIGN FEATURES 5.1. Reactor Fuel

a. The reactor fuel shall be U0 2 with a nominal enrichment of 4% in U-235, zircaloy clad, with fabrication details as described in Section 3 of the Safety Analysis Report.

b. Total bum-up on the reactor fuel is limited to 20,000 MWD/MTU.

5.2. Reactor Building

a. The reactor shall be housed in the Reactor Building, designed for confinement.

3 The minimum free volume in the Reactor Building shall be 2.25x 109 cm (refer to SAR Section 13 analysis).

b. The Reactor Building ventilation and confinement systems shall be separate from the Burlington Engineering Laboratories building systems and shall be designed to exhaust air or other gases from the building through a stack with discharge at a minimum of 100 feet above ground level.

c. The openings into the Reactor Building are the truck entrance door, personnel entrance doors, and air supply and exhaust ducts.

d. The Reactor Building is located within the Burlington Engineering Laboratory complex on the north campus of North Carolina State University at Raleigh, North Carolina. Restricted Areas as defined in 10CFR20 include the Reactor Bay, Ventilation Room, Mechanical Equipment Room, Primary Piping Vault, and Waste Tank Vault. The PULSTAR Control Room is part of the Reactor Building, however it is also a controlled access area and a Controlled Area as defined in 10CFR20. The facility license applies to the Reactor Building and Waste Tank Vault. Figure 5.2-1 depicts the licensed area as being within the operations boundary.

5.3. Fuel Storage Fuel, including fueled experiments and fuel devices not in the reactor, shall be stored in a geometrical configuration where klff is no greater than 0.9 for all conditions of moderation and reflection using light water except in cases where a fuel shipping container is used, then the licensed limit for the keff limit of the container shall apply.

40

Appendix A Amendment 18 Technical Specifications 5.4. Reactivity Control Reactivity control is provided by four neutron absorbing blades. Each control blade is nominally comprised of 80% silver, 15% indium, and 5% cadmium with nickel cladding. Three of these neutron absorbing blades are magnetically coupled and have scramming capability. The remaining neutron absorbing blade is non-scrammable. One of the scrammable rods may be used for automatic servo-control of reactor power. When in use, the servo-control maintains a constant power level as indicated by the Linear Power Channel.

5.5. Primary Coolant System The primary coolant system consists of the aluminum lined reactor tank, a N- 16 delay tank, a pump, and heat exchanger, and associated stainless steel piping. The nominal capacity of the primary system is 15,600 gallons. Valves are located adjacent to the biological shield to allow isolation of the pool, and at major components in the primary system to permit isolation.

41

Appendix A Amendment 18 Technical Specifications

... CHAMERLAIN DRIVE:

RWA E-~n ai Figure 5.2-1: NCSU PULSTAR Reactor Site Map 42

Appendix A Amendment 18 Technical Specifications 6.0. ADMINISTRATIVE CONTROLS 6.1. Organization The reactor facility shall be an integral part of the Department of Nuclear Engineering of the College of Engineering of North Carolina State University.

The reactor shall be related to the University structure as shown in Figure 6.1-1.

6.1.1. Organizational Structure:

The reporting chain is given in Figure 6.1-1. The following specific organizational levels (as defined by ANSI/ANS- 15.1-1990) and positions shall exist at the PULSTAR Facility:

Level 1 - Administration This level shall include the Chancellor, the Dean of the College of Engineering, and the Nuclear Engineering Department Head. Within three months of appointment, the Nuclear Engineering Department Head shall receive briefings sufficient to provide an understanding of the general operational and emergency aspects of the facility.

Level 2 - Facility Management This level shall include the Nuclear Reactor Program (NRP) Director. The NRP Director is responsible for the safe and efficient operation of the facility as specified in the facility license and Technical Specifications, general conduct of reactor performance and NRP operations, long range development of the NRP, and NRP personnel matters. The NRP Director evaluates new service and research applications, develops new facilities and support for needed capital investments, and controls NRP budgets.

The NRP Director works through the Manager of Engineering and Operations to monitor daily operations and with the Reactor Health Physicist to monitor radiation safety practices and regulatory compliance.

The minimum qualifications for the NRP Director are a Master of Science in engineering or physical science and at least six years of nuclear experience related to fission reactor technology. The degree may fulfill up to four years of the required six years of nuclear experience on a one-for-one time basis. Within three months of appointment, the NRP Director shall receive briefings sufficient to provide an understanding of the general operational and emergency aspects of the facility. The NRP Director is a faculty member and reports to the Nuclear Engineering Department Head.

43

Appendix A Amendment 18 Technical Specifications Level 3 - Manager of Engineering and Operations The Manager of Engineering and Operations (MEO) performs duties as assigned by the NRP Director associated with the safe and efficient operation of the facility as specified in the facility license and Technical Specifications. The MEO is responsible for coordination of operations, experiments, and maintenance at the facility, including reviews and approvals of experiments as defined in Technical Specification 1.2.9 and 6.5, and making minor changes to procedures as stated in Technical Specification 6.4. The MEO shall receive appropriate facility specific training within three months of appointment and be certified as a Senior Reactor Operator within one year of appointment. The minimum qualifications for the MEO are a Bachelor of Science in engineering or physical science and at least six years of nuclear experience related to fission reactor technology. The degree may fulfill up to four years of the required six years of nuclear experience on a one-for-one time basis. The MEO reports to the NRP Director.

Level 4 - Operating and Support Staff This level includes licensed Senior Reactor Operators (SRO),licensed Reactor Operators (RO), and other personnel assigned to perform maintenance and technical support of the facility. Senior Reactor Operators and Reactor Operators are responsible for assuring that operations are conducted in a safe manner and within the limits prescribed by the facility license and Technical Specifications, applicable Nuclear Regulatory Commission regulations, and the provisions of the Radiation Safety Committee and Reactor Safety and Audit Committee. All Senior Reactor Operators shall have three years of nuclear experience and shall have a high school diploma or successfully completed a General Education Development test. A maximum of two years equivalent full-time academic training may be substituted for two years of the required three years of nuclear experience as applicable to research reactors for Senior Reactor Operators. Other Level 4 personnel shall have a high school diploma or shall have successfully completed a General Education Development test. All Level 4 personnel report to the Manager of Engineering and Operations.

Reactor Health Physicist The Reactor Health Physicist (RHP) is responsible for implementing the radiation protection program and monitoring regulatory compliance at the reactor facility. The RHP shall have a high school diploma or shall have successfully completed a General Education Development test and have three years of relevant experience in applied radiation safety. A maximum of two years equivalent full-time academic training may be substituted for two years of the required three years of experience in radiation safety as 44

Appendix A Amendment 18 Technical Specifications applicable to research reactors. The RHP reports directly to the Nuclear Engineering Department Head and is independent of the campus Radiation Safety Division as shown in Figure 6.1-1.

6.1.2. Responsibility

Responsibility for the safe operation of the PULSTAR Reactor shall be with the chain of command established in Figure 6.1-1.

Individuals at the various management levels, in addition to having responsibility for the policies and operation of the reactor facility, shall be responsible for safeguarding the public and facility personnel from undue radiation exposures and for adhering to all requirements of the operating license, the Technical Specifications, and federal regulations.

In all instances, responsibilities of one level may be assumed by designated alternates or by higher levels, conditional upon the appropriate qualifications.

6.1.3. Minimum Staffing:

The minimum staffing when the reactor is not secured shall be:

a. A licensed reactor operator or senior reactor operator shall be present in the Control Room.

b. A Reactor Operator Assistant (ROA), capable of being at the reactor facility within five (5) minutes upon request of the reactor operator on duty.

c. A Designed Senior Reactor Operator (DSRO). This individual shall be readily available on call, meaning:

i. Has been specifically designated and the designation known to the reactor operator on duty.

ii. Keeps the reactor operator on duty informed of where he may be rapidly contacted and the telephone number.

iii. Is capable of getting to the reactor facility within a reasonable time under normal conditions (e.g., 30 minutes or within a 15 mile radius).

d. A Reactor Health Physicist or his designated alternate. This individual shall also be on call, under the same limitations as prescribed for the Designed Senior Reactor Operator under Specification 6.1.3.c.

45

Appendix A Amendment 18 Technical Specifications 6.1.4. Senior Reactor Operator Duties:

The following events shall require the presence of a licensed Senior Reactor Operator at the facility or its administrative offices:

a. Initial startup and approach to power.

b. All fuel or control rod relocations within the reactor core or pool.

c. Relocation of any in-core experiment with a reactivity worth greater than one dollar (730 pcm).

d. Recovery from unplanned or unscheduled shutdown or significant power reduction (documented verbal concurrence from a licensed Senior Reactor Operator is required).

6.1.5. Selection and Training:

All operators will undergo a selection, training and licensing program prior to unsupervised operation of the PULSTAR reactor. All licensed operators will participate in a requalification program, which will be conducted over a period not to exceed two (2) years. The requalification program will be followed by successive two (2) year programs.

46

Appendix A Amendment 18 Technical Specifications Figure 6.1-1: NCSU PULSTAR Reactor Organizational Chart memoers Incluae: . Members Include:

Radiation Safety Officer, Director NRP, RHP, and

• RSAC Chair, RHP, Member of NCSU lear Engineering Member of NRP Radiation Safety Division NOTES: Line of direct communication Line of advice and liaison mmmln Nuclear Reactor Program (NRP) includes:

" Director, NRP

• Manager, Engineering and Operations

" Operating and Support Staff Reactor Health Physicist (RHP) reports to the Head, Department of Nuclear Engineering and serves both the NRP and Department of Nuclear Engineering.

Communication on reactor operations, experiments, radiation safety, and regulatory compliance occurs between the NRP, RHP, Reactor Safety and Audit Committee, Radiation Safety Committee, and campus Radiation Safety Division as described in these Technical Specifications and facility procedures.

47

Appendix A Amendment 18 Technical Specifications 6.2. Review and Audit The Radiation Safety Committee (RSC) has the primary responsibility to ensure that the use of radioactive materials and radiation producing devices, including the nuclear reactor, at the University are in compliance with state and federal licenses and all applicable regulations. The RSC reviews and approves all experiments involving the potential release of radioactive material conducted at the University and provides oversight of the University Radiation Protection Program. The RSC is informed of the actions of the Reactor Safety and Audit Committee (RSAC) and may require additional actions by RSAC and the Nuclear Reactor Program (NRP).

RSAC has the primary responsibility to ensure that the reactor is operated and used in compliance with the facility license, Technical Specifications, and all applicable regulations. RSAC performs an annual audit of the operations and performance of the NRP.

6.2.1. RSC and RSAC Composition and Qualifications:

a. RSC shall consist of members from the general faculty who are actively engaged in teaching or research involving radioactive materials or radiation devices. RSC may also include non-faculty members who are knowledgeable in nuclear science or radiation safety.

RSC membership shall include the University Radiation Safety Officer, RSAC Chair, RHP, and a member of the NRP.

b. RSAC shall consist of at least five individuals who have expertise in one or more of the component areas of nuclear reactor safety. These include Nuclear Engineering, Nuclear Physics, Health Physics, Electrical Engineering, Chemical Engineering, Material Engineering, Mechanical Engineering, Radiochemistry, and Nuclear Regulatory Affairs.

At least three of the RSAC members are appointed from the general faculty. The faculty members shall be as follows:

i. NRP Director ii. One member from an appropriate discipline within the College of Engineering iii. One member from the general faculty 48

Appendix A Amendment 18 Technical Specifications The remaining RSAC members are as follows:

iv. Reactor Health Physicist (RHP)

v. Member from the campus Radiation Safety Division of the Environmental Health and Safety Center vi. One additional member from an outside nuclear related establishment may be appointed At the discretion of RSAC, specialist(s) from other universities and outside establishments may be invited to assist in its appraisals.

The NRP Director, RHP, and a member from the campus Radiation Safety Division of the Environmental Health and Safety Center are permanent members of RSAC.

6.2.2. RSC and RSAC Rules

a. RSC and RSAC committee member appointments are made by University Management for terms of three (3) years.

b. RSC shall meet as required by the broad scope radioactive materials license issued to the University by the State of North Carolina. RSC may also meet upon call of the committee Chair.

c. RSAC shall each meet at least four (4) times per year, with intervals between meetings not to exceed six months. RSAC may also meet upon call of the committee Chair.

d. A quorum of RSC or RSAC shall consist of a majority of the full committee membership and shall include the committee Chair or a designated alternate for the committee Chair. Members from the line organization shown in Figure 6.1 -1 shall not constitute a majority of the RSC or RSAC quorum.

49

Appendix A Amendment 18 Technical Specifications 6.2.3. RSC and RSAC Review and Approval Function

a. The following items shall be reviewed and approved by the RSC:

i. All new experiments or classes of experiments that could result in the release of radioactivity.

ii. Proposed changes to the facility license or Technical Specifications, excluding safeguards information.

b. The following items shall be reviewed and approved by the RSAC:

i. Determinations that proposed changes in equipment, systems, tests, experiments, or procedures which have safety significance meet facility license and Technical Specification requirements.

ii. All new procedures and major revisions having safety significance, proposed changes in reactor facility equipment, or systems having safety significance.

iii. All new experiments or classes of experiments that could affect reactivity or result in the release of radioactivity.

iv. Proposed changes to the facility license or Technical Specifications, including safeguards information.

c. The following items shall be reviewed by the RSC and RSAC:

i. Violations of the facility license or Technical Specifications ii. Violations of internal procedures or instructions having safety significance.

iii. Operating abnormalities having safety significance.

iv. Reportable Events as defined in Specification 1.2.24.

Distribution of RSC summaries and meeting minutes shall include the RSAC Chair and Director of the Nuclear Reactor Program.

A summary of RSAC meeting minutes, reports, and audit recommendations approved by RSAC shall be submitted to the Dean of the College of Engineering, the Nuclear Engineering Department Head, the Director of the Nuclear Reactor Program, the RSC Chair, Director of Environmental Health and Safety, RSAC Chair, and the Manager of Engineering and Operations prior to the next scheduled RSAC meeting.

50

Appendix A Amendment 18 Technical Specifications 6.2.4. RSAC Audit Function The audit function shall consist of selective, but comprehensive, examination of operating records, logs, and other documents. Discussions with cognizant personnel and observation of operations shall also be used as appropriate. The RSAC shall be responsible for this audit function. In no case shall an individual immediately responsible for the area perform an audit in that area. This audit shall include:

a. Facility operations for conformance to the facility license and Technical Specifications, annually, but at intervals not to exceed fifteen (15) months.

b. The retraining and requalification program for the operating staff, biennially, but at intervals not to exceed thirty (30) months.

c. The results of actions taken to correct those deficiencies that may occur in the reactor facility equipment, systems, structures, or methods of operations that affect reactor safety, annually, but at intervals not to exceed fifteen (15) months.

d. The Emergency Plan and Emergency Procedures, biennially, but at intervals not to exceed thirty (30) months.

e. Radiation Protection annually, but at intervals not to exceed fifteen (15) months.

Deficiencies uncovered that affect reactor safety shall be immediately reported to the Nuclear Engineering Department Head, Director of the Nuclear Reactor Program, and the RSC.

The annual audit report made by the RSAC, including any recommendations, is provided to the RSC.

6.3. Radiation Safety The Reactor Health Physicist (RIHP) is responsible for implementing the radiation protection program and monitoring regulatory compliance at the reactor facility.

The RHP reports directly to the Nuclear Engineering Department Head and is independent of the campus Radiation Safety Division as shown in Figure 6.1-1.

51

Appendix A Amendment 18 Technical Specifications 6.4. Operating Procedures Written procedures shall be prepared, reviewed and approved prior to initiating any of the following:

a. Startup, operation and shutdown of the reactor.

b. Fuel loading, unloading, and movement within the reactor.

c. Maintenance of major components of systems that could have an affect on reactor safety.

d. Surveillance checks, calibrations and inspections required by the facility license or Technical Specifications or those that may have an affect on the reactor safety.

e. Personnel radiation protection, consistent with applicable regulations and that include commitment and/or programs to maintain exposures and releases as low as reasonably achievable (ALARA).

f. Administrative controls for operations and maintenance and for the conduct of irradiations and experiments that could affect reactor safety or core reactivity.

g. Implementation of the Emergency Plan and Security Plan.

Substantive changes to the above procedures shall be made effective only after documented review and approval by the RSAC and by the Manager of Engineering and Operations.

Minor modifications to the original procedures which do not change their original intent may be made by the Manager of Engineering and Operations, but the modifications shall be approved by the Director of the Nuclear Reactor Program within fourteen (14) days.

Temporary deviations from procedures may be made by Designed Senior Reactor Operator as defined by Specification 6.1.3.c or the Manager of Engineering and Operations, in order to deal with special or unusual circumstances or conditions.

Such deviations shall be documented and reported to the Director of the Nuclear Reactor Program.

52

Appendix A Amendment 18 Technical Specifications 6.5. Review of Experiments 6.5.1. New (untried) Experiments All new experiments or class of experiments, referred to as "untried" experiments, shall be reviewed and approved by the RSC, the RSAC, the Director of the Nuclear Reactor Program, Manager of Engineering and Operations, and the Reactor Health Physicist, prior to initiation of the experiment.

The review of new experiments shall be based on the limitations prescribed by the facility license and Technical Specifications and other Nuclear Regulatory Commission regulations, as applicable.

6.5.2. Tried Experiments All proposed experiments are reviewed by the Manager of Engineering and Operations and the Reactor Health Physicist (or their designated alternates). Either of these individuals may deem that the proposed experiment is not adequately covered by the documentation and/or analysis associated with an existing approved experiment.and therefore constitutes an untried experiment that will require the approval process detailed under Specification 6.5.1.

If the Manager of Engineering and Operations and the Reactor Health Physicist concur that the experiment is a tried experiment, then the request may be approved.

Substantive changes to previously approved experiments will require the approval process detailed under Specification 6.5.1.

53

Appendix A Amendment 18 Technical Specifications 6.6. Required Actions 6.6.1. Action to be Taken in Case of Safety Limit Violation In the event a Safety Limit is violated:

a. The reactor shall be shutdown and reactor operations shall not be resumed until authorized by the Nuclear Regulatory Commission.

b. The Safety Limit violation shall be promptly reported to the Director of the Nuclear Reactor Program, or his designated alternate.

c. The Safety Limit violation shall be reported to the Nuclear Regulatory Commission in accordance with Specification 6.7.1.

d. A Safety Limit violation report shall be prepared that describes the following:

i. Circumstanced leading to the violation including, when known, the cause and contributing factors.

ii. Effect of violation upon reactor facility components, systems, or structures and on the health and safety of facility personnel and the public.

iii. Corrective action(s) to be taken to prevent recurrence.

The report shall be reviewed by the RSC and RSAC and any follow-up report shall be submitted to the Nuclear Regulatory Commission when authorization is sought to resume operation.

6.6.2 Action to be Taken for Reportable Events (other than SL Violation)

In case of a Reportable Event (other than violation of a Safety Limit), as defined by Specification 1.2.24, the following actions shall be taken:

a. Reactor conditions shall be returned to normal or the reactor shall be shutdown. If it is necessary to shutdown the reactor to correct the occurrence, operation shall not be resumed unless authorized by the Director of the Nuclear Reactor Program, or his designated alternate.

b. The occurrence shall be reported to the Director of the Nuclear Reactor Program, and to the Nuclear Regulatory Commission in accordance with Specification 6.7.1.

c. The occurrence shall be reviewed by the RSC and RSAC at their next scheduled meeting.

54

Appendix A Amendment 18 Technical Specifications 6.7. Reporting Requirements 6.7.1. Reportable Event For Reportable Events as defined by Specification 1.2.24, there shall be a report not later than the following work day by telephone to the Nuclear Regulatory Commission Operations Center followed by a written report within fourteen (14) days that describes the circumstances of the event.

6.7.2. Permanent Changes in Facility Organization Permanent changes in the facility organization involving either Level 1 or 2 personnel (refer to Specification 6.1. 1) shall require a written report within thirty (30) days to the Nuclear Regulatory Commission Document Control Desk.

6.7.3. Changes Associated with the Safety Analysis Report Significant changes in the transient or accident analysis as described in the Safety Analysis Report shall require a written report within thirty (30) days to the Nuclear Regulatory Commission Document Control Desk.

6.7.4. Annual Operating Report An annual operating report for the previous calendar year is required to be submitted no later than March 3 1st of the present year to the Nuclear Regulatory Commission Document Control Desk. The annual report shall contain as a minimum, the following information:

a. A brief narrative summary:

i. Operating experience including a summary of experiments performed.

ii. Changes in performance characteristics related to reactor safety that occurred during the reporting period.

iii. Results of surveillance, tests, and inspections.

b. Tabulation of the energy output (in megawatt days) of the reactor, hours reactor was critical, and the cumulative total energy output since initial criticality.

c. The number of emergency shutdowns and unscheduled SCRAMs, including reasons and corrective actions.

55

Appendix A Amendment 18 Technical Specifications

d. Discussion of the corrective and preventative maintenance performed during the period, including the effect, if any, on the safety of operation of the reactor.

e. A brief description, including a summary of the analyses and conclusions of changes in the facility or in procedures and of tests and experiments carried out pursuant to 10CFR50.59.

f. A summary of the nature and amount of radioactive effluent released or discharged to the environs beyond the effective control of the licensee as measured at or prior to the point of such release or discharge, including:

Liquid Waste (summarized by quarter)

i. Radioactivity released during the reporting period:

1. Number of batch releases.

2. Total radioactivity released (in microcuries).

3. Total liquid volume required (in liters).

4. Diluent volume required (in liters).

5. Tritium activity released (in microcuries)

6. Total (yearly) tritium released.

7. Total (yearly) activity released.

ii. Identification of fission and activation products:

Whenever the undiluted concentration of radioactivity in the waste tank at the time of release exceeds 2x 10-5 VtCi/ml, as determined by gross beta/gamma count of the dried residue of a one liter sample, a subsequent analysis shall also be performed prior to release for principle gamma emitting radionuclides. An estimate of the quantities present shall be reported for each of the identified nuclides.

iii. Disposition of liquid effluent not releasable to the sanitary sewer system:

Any waste tank containing liquid effluent failing to meet the requirements of IOCFR20, Appendix B, to include the following data:

1. Method of disposal.

2. Total radioactivity in the tank (in microcuries) prior to disposal.

56

Appendix A Amendment 18 Technical Specifications

3. Total volume of liquid in tank (in liters).

4. The dried residue of one liter sample shall be analyzed for the principle gamma-emitting radionuclides. The identified isotopic composition with estimated concentrations shall be reported. The tritium content shall be included.

Gaseous Waste

i. Radioactivity discharged during the reporting period (in curies) for:

1. Gases

2. Particulates, with half lives greater than eight days.

ii. The Airborne Effluent Concentration (AEC) used and the estimated activity (in curies) discharged during the reporting period, by nuclide, for all gases and particulates based on representative isotopic analysis. (AEC values are given in 10CFR20, Appendix B, Table 2.)

Solid Waste

i. The total amount of solid waste packaged (in cubic feet).

ii. The total activity involved (in curies).

iii. The dates of shipment and disposition (if shipped off-site).

g. A summary of radiation exposures received by facility personnel and visitors, including pertinent details of significant exposures.

h. A summary of the radiation and contamination surveys performed within the facility and significant results.

i. A description of environmental surveys performed outside the facility.

57

Appendix A Amendment 18 Technical Specifications 6.8. Retention of Records Records and logs of the following items, as a minimum, shall be kept in a manner convenient for review and shall be retained as detailed below. In addition, any additional federal requirement in regards to record retention shall be met.

6.8.1 Records to be retained for a period of at least five (5) years:

a. Normal plant operation and maintenance.

b. Principal maintenance activities.

c. Reportable Events.

d. Equipment and components surveillance activities as detailed in Specification 4.

e. Experiments performed with the reactor.

f. Changes to Operating Procedures.

g. Facility radiation and contamination surveys other than those used in support of personnel radiation monitoring.

h. Audit summaries.

i. RSC and RSAC meeting minutes.

6.8.2 Records to be retained for the life of the facility:

a. Gaseous and liquid radioactive waste released to the environs.

b. Results of off-site environmental monitoring surveys.

c. Radiation exposures for monitored personnel and associated radiation and contamination surveys used in support of personnel radiation monitoring.

d. Fuel inventories and transfers.

e. Drawings of the reactor facility.

6.8.3 Records to be retained for at least one (1) license period of six (6) years:

Records of retraining and requalification of certified operating personnel shall be maintained at all times the individual is employed, or until the certification is renewed.

58

ATTACHMENT 1 FUELED EXPERIMENT ANALYSIS TECHNICAL SPECIFICATIONS AMENDMENT 18 TABLE OF CONTENTS Topic Page Introduction 2 Assumptions and Data Sources 3 Source Term (fission product inventory) 5 Radioactive Decay Branching Data 14 Fission Yield Data 16 Fission Cross-Section Data 17 Validation of Atom Population Calculations 19 Released Activity 20 Concentration and Time-Integrated Exposure 21 Dose Assessment 22 Experiment Limits 23 Mass Limits- 26 Energy Release 27 Example Calculations 28 Detailed Sample Calculation: Thermal Fission of U-235 41 Dose Results for Dry and Wet Samples 44 Results for Limiting Fission Rates 49 Comparison of Source Term to Nuclear Analysis 1.0 54 Comparison of Fission Rates to Amendment 17 59 Conclusions 61

/

I

INTRODUCTION Fueled experiments are defined in Technical Specifications (TS) as experiments that contain fissionable material. TS 3.8 on fueled experiments in Amendment 17 limits fueled experiments to those that contain only U-235. Numerous fissionable materials are included in this analysis in support of TS Amendment 18 to provide limiting conditions for two categories of fissionable materials; (1) U and Pu and (2) All Others. U and Pu are placed in a separate category since various isotopic enrichments of these elements are commonly used.

Limitations for a fueled experiment are based on potential radiation dose and other experimental limitations, e.g. reactivity, heat, pressure. This analysis is concerned only with potential radiation doses to workers and members of the public following an accidental release of fission products from a failed fueled experiment. All conditions for fueled experiments must be met as stated in TS 3.8 for the experiment to be conducted.

The accident scenario considered for fueled experiments is the release of fission products produced from initially pure fissionable material into the reactor bay. Production periods from 10 seconds to 1 year with no decay and with decay periods up to 1 year were analyzed. The fission product inventory is assumed to be instantaneously and uniformly distributed throughout the entire reactor bay air space at the time of the accident and then exhausted to the environment by the confinement filters and reactor stack. Based on this scenario, the concentration in the reactor bay, confinement filter retention, and atmospheric dispersion are considered. Wet and dry irradiations were considered as well. As a result of the need for filtered ventilation, an exhaust stack, and radiation monitoring of the ventilation system, fueled experiments are excluded from being performed in experimental facilities located outside the reactor building.

Whole body and thyroid doses are calculated for personnel in the reactor building and whole body dose is calculated for members of the public. Dose is limited to 10% of the applicable annual limits.

Based on the analysis, the fissionable material resulting in the most limiting dose is used as the basis for TS 3.8 in Amendment 18.

Up to 10% of the applicable dose limits is a reasonable limitation based on requirements for an official regulatory response, i.e. monitoring of occupational personnel and reporting of doses in excess of the constraint dose for members of the public. Regulatory Guide 2.2 also indicates limiting doses to 10% of the applicable limits for experiments performed at research reactors.

2

ASSUMPTIONS and DATA SOURCES Assumed conditions for a fueled experiment are as follows:

" Fissionable material is encapsulated until the time of failure. After the accidental release occurs no credit is taken for encapsulation

• Neutron flux density is constant over time and for the entire mass of the fissionable material

" No loss from the encapsulation occurs until the time of failure

" Failure of dry fueled experiments result in a complete release of the entire fission product inventory into the reactor building free air volume

" Failure of wet fueled experiments results in a complete release of noble gases and 25%

release of halogens to the reactor building free air volume (ref. ANSUANS 15-7)

" Reactor ventilation system is in the confinement mode (TS 3.8 requirement)

• Initially pure fissionable material is exposed, i.e. there is no initial inventory of fission products

" Exposure times to personnel in the reactor building and to the public are estimated as 0.25 h and 24 h, respectively based on evacuation time from the reactor building and reactor building exhaust rates in the confinement mode.

" No credit for respiratory protection is assumed.

" The release is assumed to occur instantaneously

" The reactor building free air volume is approximated at 2 E9 ml (Ref: FSAR).

• Confinement filter retention is 99.97% for particulates and 90% for halogens (Ref: FSAR and NUREG 1537)

" Atmospheric dispersion parameter, X/Q at 1 m/s for Class F weather stability and a release time of 24 h is 0.0076 s m-3 for the PULSTAR reactor based on ANSI/ANS 15-7 methodology (as determined in TS Amendment 17)

" Buildup and fission of transuranics is neglected

• Depletion by transmutation of fission products and fissionable materials (i.e. bumup) is neglected Data for radionuclides and fission products were taken from the following sources:

• Evaluation and Compilation of Fission Product Yields, T.R. England and B.F. Rider, Los Alamos National Laboratory, October, 1994, LA-UR 94-3106 ENDF 349

• Standards for Protection Against Radiation, Appendix B, 10 CFR 20

• National Nuclear Data Center, Brookhaven National Laboratory, Evaluated Nuclear Data Files (ENDF libraries)

" Japan Atomic Energy Agency Nuclear Data Center Tables of Nuclear Data (JENDL data)

" NEA Publication 6287, Joint Evaluated Fission and Fusion Project Report 20 (JEFF 3.1-3.1.1 Radioactive Decay Data and Fission Yield Sub-Library)

Weather conditions for accidental releases as stated in ANSI/ANS 15-7 are assumed:

• Class F weather stability

" 1 m/s (2.24 mph) wind speed

• No wind direction change (i.e. no cross wind averaging or sector averaging)

" Stack height of 30 m (i.e. actual and effective stack height approximately the same) 3

Major steps for calculation of potential dose from a failed fueled experiment include the following:

1. Number of fission product atoms produced during irradiation time (t)

2. Activity of fission products after irradiation and decay time (t + T)

3. Released activity and airborne concentrations of fission products in dry and wet experimental conditions

4. Filtration of fission products by the confinement system

5. Fission rate in the fissionable material potentially resulting in 10% of the occupational and public dose limits for the whole body and 10% of the occupational dose limits for the thyroid 4

SOURCE TERM The number of atoms, N, for a given radionuclide in a serial transformation, such as a fission product decay chain, is calculated as described below (Ref: Health Physics Journal, 27, 155, Skrable et.al.

1974) during the time of production, "t":

,G al Equaton for the.Kinetics .of L ear q T:,First Order.:Phenomena Consider' the .serial transformation by any linear firt order process of each member in.the series:

.. ' ,t3/4 i,, 2 .,

t'"

IV,! qu*antity -of the 'ispecies present* at a particlar ti*me, t, total cmoval constant for the j" species (i.e. the intantaneous fracon of te i4a spes destroyed per unit time.,by alllinear:

first order removal processcs),

k *kil)=

partial ;removal constant, for the :-Uh:species ie.the: insananeu0s: frction- of -the.-"

speicies transfoned= per unt tine:to the (i + 1).1. species), and related to :the bra*ncing fnaction, f(, .*):

cons-tant i nd.ependenit rate: of produicdoition o the *, species.

5

The differential equations for the intantaneous "timerates of change in the quantities of each member

.of the chain-are:

dN1 a* ="i -k 1 N*

dNX 2 P. + k41 2 N -N -

PlDwk( LVL citvn,.nm'nt r (l-) n-SThese.6eqiuations may be -solved by standard methods.

. obtain thIe quantity of any member of the series.

The general equation for the quantity of the i"n mebef-r of-theseries is given by.

J --n N.. .. .. -.

wh'er'e.

Ni.. =.quantity Ofjth specispresent at somearbitrary

,referencetiime zero, and t =-generation or elapsed time.

6

If Ni° is initially zero for all fission product atom populations (as would be the case for the assumption of initially pure fissionable materials), then the above equation is simplified to the following:

7 j=P(-e J) i=n f (j,j+l) X J=i kj irf (kp - kj )

J=t p=n p~j where, i ranges from 1 to n to account for all members of the decay chain leading to the formation of the nth atom population, j and p are used as indices for i to account for the number of nth atoms originating from the ith atom population Noting that P depends on "i", which ranges from i=1 to i=n and that for a given decay chain a decay branching fraction, B, and that radioactive decay is the only removal process that leads to the next radionuclide gives the following:

j=n-1 j=n 1 e(-Ait)

Nn(t = Hin p=n j=i j=i p=i p~j where, Xis the radioactive decay constant equivalent to the total removal rate constant k, B is the decay branch fraction leading to the succeeding radionuclide, Bjkj is the partial rate constant leading to the next member of the decay chain equivalent to the parameter kj~j+l ( i.e. kj,j+l = Xj

• fj,j+,)

11-For example if n = 2, the above equation gives the following:

+ 1 e( - 2 )

1+P

__l ___

Nd,(2 A /1 2 /12

and, 7

Convergent and-Divergent RBranc*hes Ifa given quantity.in a.series is produced by a first orderprocess from some brancingichain,' then by applicatiognofequaion (I) over all applicable c.hai, itpiws ;ibl.e to obtain:the total ,valu.eof this.,qu tity by simple, addition of values: calculated- from the var ious chains 4 Hwcever, in: calcula*tigthe quantifty.

of te n"': spe~ci~es firom variu conrbuting chis the: last . term" in the: major sutmamation,- which.iss calcuiatAedfor i.= n, should not be added:more than once since it represents contribution off the nth- species toitsel* Similar considerations apply toany species following the. nt*species. Divergent branches. can be treated independeritly to yield quantities.of interest.

Altered radioactive decay pathways occur frequently with metastable nuclides and delayed neutron emitting nuclides. For example consider the following fission product series producing N4(t) formed by fission with no initial radioactive inventory, (i.e. Nn(O) is 0):

8

From the discussion on branching given above, N4(t) is calculated as follows for the two pathways leading to N4(t):

(1) Nl--+N2--*N3--ýN4 (2) Ni -- N2-~N3m-+N3-+ýN4 N4(t)= IB~kB 2k2 B~k

[1 k (k2-k)(k_ - e(-klt) 3-k)(k4 -k,) k2 (k, -k 21)(k - 3 - k2 )(k 4 -k 2) e(-k2) 1- e(-k3t) k3(k, -k 3 )(k2 - k3 )(k4 - k 3 )

+

1 e(-k4t) k 4 (kI -k 4 )(k 2 - k 4 )(k 3 - k 4 ) I

+ P2B2k 2B3k 3 rk2(k 31E~

ek

-k2 0( 4-_k

-k 2)+

2) k3(k2 -k3)(k

- ++

1-e(-3t) -_k) k(2k)k1-e(-k,1) k) 4 3 k 2 k 4- k4) 1- e(-k3t)

+ 1-4 (k_4t) + P4 1- (k4) + PPBikIB 2k 2B3mk 3mB3k 3X

+ P3B3k3 k3(k4 -k 3) k4(3- 4) kI lIe(-k2t)

I +e k2 (k 1 -k 2 )(k3 m-k 2 )(k3 -k 2 )(k 4 -- k2) 1-ee(k3.t) .4-1- (-kt) k3m(kI - k 3m)(k 2- k 3m)(k 3- k 3m)(k 4- k 3m) k 3 (k, - k 3 )(k 2 - k 3 )(k 3m - k3 )(k 4 - k 3 )

1 -e-k4) 1 1-e(-k2t) k4(kl - k4 )(k 2 -k 4)(k 3m -k 4 )(k 3 -Ik4 )]

+ P2B 2k2B3.k3.B3k3 L ki(k 3m,- k2 )(k3 -k 2)(k4 -I 2) 1- (-k3.t) 1-e(-k3t)

-I- I I k 3m(k2 - k 3 )(k 3 - k 3m)(k 4 - k3) k 3 (k 2 k3 )(k 3 m-k 3 )(k 4 -k 3) 1- e (-k3.')

+ k -)- e(-k4 )

k4(k 2 - k4)1)(4k3-k4)

.+ P3 mB2k2B3k3 Lk I3m 3. ( k3 m)(k 4 - k 3m) 1- e(-k3t) 1- e(-k4t)

+ k3(k3m-k 3)(k4 -k3 ) + (k- )(-k) + PFB 3k 3 1 - e(k3) 1- (-k4t)_

k3(k4 -k 3 ) k 4 (k3-k 4 )j 9

Similarly, N3(t) is given by the following:

N3(=I 1-e (-k1 - e(-k2l) 1 - e(-k3-)

N 3 (t) = *B'k 1B2k 2 Lkl(k 2 k,)(k  ; 3 -k,) +k 2 (k, -k2 )(k3 -k 2 ) + k3(k.-k 3 )(k2 -k 3 )j 2"k 2 2-k -

EB 1e-k + 1-ek(-k 3l) + P3 [1-e 1-e-'k3]

1 k2(k3 -k2) k3(k2 - k3)] k3 Lki(k2 ki)(k 3 k- 3 -)(k k) k2 (k, -k 2 )(k3*-k 2 )(k 3 - k2 )

+ 1- e(~~ + 1-ee(k3t)

+ p2g2k2B3mk3m k 1-e (-k) +( 1 -e (-k 3.)

kI(ki-k 1- )(k 2 -km e-k2l) 2)(k 3 k2)L 1-e

,(k e(k3.t)1-

"k3)(kkm-kk) kl)

+P~kB 223m~mm

+3 ( l -e3(k3 k) ] km(k 3 -k 2 m)(kk 3 3 3) l-k NOTE: k is the total removal rate constant, B is the decay branch fraction and Bk is the partial rate constant, If radioactive decay is the only removal mechanism, then k = X Pi is given by the product OTarget () NTarget Yi 0

where, Target is the fission cross section for the target atoms, p is the neutron fluence rate, which is assumed to be constant and uniform, NTaiget is the number of target atoms available to undergo fission, Yi is the fission yield for nuclide "i" 10

The above equations apply to "t", the time of production, and account for the number of atoms produced directly from fission and by decay of precursors during "t".

Atoms continue to be produced by the decay of precursors following production, or during decay time "T".

The graph below indicates buildup and decay of radioactive material during production time "t" with decay following production during time "T". With the decay of precursors the activity of a given nuclide may continue to increase during "T".

e.g. Sr-91 and Y-91 atoms populations are shown below for a production time (t) of 20 h (fission irradiation time). The atom population of Y-91 continues to increase during the decay time (T) from the decay of Sr-91 following production.

0.71E+10 5.37E -10 .. .. . . .. . . .. . . .. . . .. -------.. .. . . . .. . ... .........--- . ............... . . . . . . . .. . . . . . . .

4.0{3e+16 .......... ... ... ... ---- - - - - - - - -- - - - ....... - - - -...............

. . . . . . . . . . .I.................

6.04E+10 --- - -- - -- - - - - - - -- - - - -- - - --

2 .N8E*10 --------- -- ... . ............. *............... J- . . . ...............

2.01E 10 ..... ..... ..... ... .-..... .... ...-................ L; ............... ............... ............... ............... ................

2 1.3E#1t - - - . . . -- - -- - - - - -- - - - -- - - - . . . . . . . . . . ............. i......... ........ i.----------------

6.71E.00 ........ *................... .. .. ... ... ....--... ... ... ...--...-- ...--------.

00 2,OE01 4,0E01 6.01E01 O.OETO1 1.0 IE102 ' I .V2 I.St02 2.0Ei02 Time (Hours)

Strotium-9l1 Yttium-l1 11

Following production, radioactive decay occurs. Consider the following radioactive decay series:

AI A 2 23 N 1 -> N2 -> N 3 --> N 4 In this decay chain, a radionuclide decays consecutively through a series of radionuclides to a stable nuclide. The net rate of change of each nuclide in the decay chain is:

dN1 =-AIN dt dN 2 _ + N1 dt dN dt A3 33 k 2 dN4 :.N dt The solutions to these equations are:

0 t N,(t) = N, e-N 2 (t): N1° (e- At e-xt)

N3W=A NOe-Alt +e-*t +e- t3 1 N 3 (t) : A1AzNI [ e° +

N 4(t) = N1 °(1- e-"') - (N 2 + N 3) from material balance In the general case of a radioactive decay chain:

N, 2N 12

The amount Ni of any nuclide present at time t can be written by analogy, if N(O) > 0 and Ni(0) = 0 for i > 1:

NNi~t Il2 = ..* AiINOi 22"* i-II°Z k=i e-Ait (i>1) 171 (k -/1j) k=I,k~j In the case of production by fission during time "t" followed by decay period "T", and if radioactive decay is the only removal mechanism resulting in the next nuclide, then the atom population is given by the following:

i=n j=n-1 i=n *j(t+T))

e (-

Nn (t + T) = I Ni (t) f Bj/jI p=n i=1 j=i j=l p=i p ::j where, N,(t+T) is the atom population after decay time T post-production Ni(t) is the atom population at the end of production B is the decay branching fraction Xis the radioactive decay constant For example if n=2, the above equation gives the following:

exp(-/lT) +exp(-A2T)

N 2 (t + T) = N, (t)B-/1 1 + N2 (t[exp(-/,2T)]

and, N, (t + T) = N1 (t)[exp(-2q T)]

Each decay pathway leading to N must be analyzed, i.e. divergent and convergent pathways are analyzed as previously described.

13

Values of N for fission product decay chains for atomic masses from A = 66 to A =167 from the thermal and fast fission of various materials were determined as described above. The number of radionuclides evaluated was approximately 500.

DECAY BRANCHING FRACTIONS Data from NEA Publication 6287 "Joint Evaluated Fission and Fusion Project Report 20" (JEFF 3.1-3.1.1 Radioactive Decay Data and Fission Yield Sub-Library) was used for the various decay branching fractions. These include the following:

B- Beta minus decay B-m Beta minus decay leading to 1st level metastable decay product B-,n Beta minus decay with delayed neutron B-,nm Beta minus decay with delayed neutron leading to metastable decay product IT Isomeric transition with gamma photon emission Many of the fission products undergo beta minus decay and delayed neutron emission. For example the B-, B-,n and B-, 2n decay of Br-94 is shown below:

P-delayed In and 2n emission from 4Br 13340 - 2n

! 8500 ]. --

5200t 4)K *, 9"Kr

"'Kr Example decay chain: A = 133 Sn-133 Sb-133 T-133m Te-133m*

1-133 Xe-133\

Stable C.-133 14

Decay Chains and Data for A = 133:

1. Sn-133 to Sb-133 to Te-133m to Te-133 to 1-133 to Xe-133m to Xe-133

2. Sn-133 to Sb-133 to Te-133m to Te-133 to 1-133 to Xe-133

3. Sn-133 to Sb-133 to Te-133m to 1-133 to Xe-133m to Xe-133

4. Sn-133 to Sb-133 to Te-133m to 1-133 to Xe-133

5. Sn-133 to Sb-133 to Te-133 to 1-133 to Xe-133m to Xe-133

6. Sn-133 to Sb-133 to Te-133 to 1-133 to Xe-133 Yield per Branching 100 fissions Decay Decay Nuclide Half-life (s) for U-235 Constant (1/s) Fraction Sn133 1.44E+00 1.38E-01 4.81 E-01 1 (B)

Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 (i,m)

Tel 33m 3.32E+03 2.99E+00 2.09E-04 0.175 (IT)

Te133 7.44E+02 1.15E+00 9.32E-04 1 (B) 1133 7.49E+04 1.65E-01 9.26E-06 0.0285 (B,m)

Xel33m 1.89E+05 1.89E-03 3.66E-06 1 (IT)

Xe133 4.53E+05 6.66E-04 1.53E-06 1 (B)

Sn133 1.44E+00 1.38E-01 4.81 E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 Tel33m 3.32E+03 2.99E+00 2.09E-04 0.175 Te133 7.44E+02 1.15E+00 9.32E-04 I 1133 7.49E+04 1.65E-01 9.26E-06 0.9715 (B)

Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81 E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 Tel33m 3.32E+03 2.99E+00 2.09E-04 0.825 (B) 1133 7.49E+04 1.65E-01 9.26E-06 0.0285 Xel33m 1.89E+05 1.89E-03 3.66E-06 1 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81 E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 Tel 33m 3.32E+03 2.99E+00 2.09E-04 0.825 1133 7.49E+04 1.65E-01 9.26E-06 0.9715 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.8271 (B)

Te133 7.44E+02 1.15E+00 9.32E-04 1 1133 7.49E+04 1.65E-01 9.26E-06 0.0285 Xel33m 1.89E+05 1.89E-03 3.66E-06 1 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81 E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.8271 Te133 7.44E+02 1.15E+00 9.32E-04 1 1133 7.49E+04 1.65E-01 9.26E-06 0.9715 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Where, (B) is beta minus decay, (B,m) is beta minus decay to isomer, (IT) is isomeric transition 15

FISSION YIELD DATA Individual thermal neutron fission yields for the following materials were evaluated:

Th-227, 229 U-232, 233,235 Np-237 Pu-239, 240, 242 Am-241, 242 Cm-245 Cf-249, 251 Fm-255 Individual fast neutron fission yields for the following materials were evaluated:

Pa-231 Th232 U-233,234, 235, 236, 237, 238 Np-238 Pu-238, 239, 240, 241, 242 Am-241, 243 Cm-242, 243, 244, 246, 248 Cf-249, 251 Fission yields were taken from data given in "Evaluation and Compilation of Fission Product Yields, T.R. England and B.F. Rider, Los Alamos National Laboratory, October, 1994, LA-UR 94-3106 ENDF 349" and in the JAEA Nuclear Data Center Tables of Nuclear Data. If available, JAEA data for fission yields was used for data not given in ENDF 349. Example fission yield data from ENDF 349 is shown below:

Fission Product Yields per 100 Fissions for 235U Thermal Neutron Induced Fission Decay, T.R. England and B.F. Rider, LA-UR-94-3106, ENDF-349 Nuclide tl/2 Ind. Yield Cum. Yield 99Sr 0.269s 1.33E-01 1.33E-01 99Y 1.47 s 1.95E+00 2.08E+00 99Zr 2.2 s 3.58E+00 5.63E+00 99Nb-m 2.6 m 4.07E-01 2.10E+00 99Nb 15.0 s 3.OOE-02 3.97E+00 99Mo 2.748d 4.28E-02 6.11E+00 99Tc-m 6.01 h 2.89E-08 5.38E+00 99Tc 2.le5y 1.23E-07 6.11E+00 137Sn 1.86E-05 1.86E-05 137Sb 0.478s 7.43E-02 7.44E-02 137Te 2.5 s 3.92E-01 4.53E-01 1371 24.5 s 2.62E+00 3.07E+00 137Xe 3.82 m 3.19E+00 6.13E+00 137Cs 30.17y 6.OOE-02 6.19E+00 137Ba-m 2.552m 1.33E-04 5.85E+00 16

FISSION CROSS-SECTION DATA Thermal fission cross sections were taken at 0.025 eV and fast fission cross sections were taken at peak values from 0.5 eV to 100 eV. Fission cross-section (n,f) values were taken from the library ENDF /B VII. 1 available at http://www.nndc.bnl.gov/ and http://www.nndc.bnl.gov/sigma/.

Fission Cross Section Data from ENDF/B-VII.1 Thermal Fission Fast Fission Nuclide Cross Section (b) Cross Section (b)

Th-227 202 Th-229 31 376 at 7 eV U-232 77 3507 at 12.6 eV U-233 532 870 at 1.7 eV U-235 585 673 at 19.3 eV Np-237 0.02 6.2 at 41 eV Pu-239 751 594 at 66 eV Pu-240 0.064 23 at 1 eV Pu-242 0.014 2.55 at 2.7 eV Am-241 3.12 47.4 at 1.27 eV Am-242 2104 Cm-245 2063 1458 at 7.5 eV Cf-249 1678 5962 at 0.7 eV Cf-251 4948 8233 at 0.3 eV Fm-255 3362 Th-232 3.8 E-6 at 4 eV Pa-231 0.26 at 55 eV U-234 13.8 at 5.1 eV U-236 157 at 5.4 eV U-237 394 at 5 eV U-238 0.016 at 21 eV Np-238 959 at 1 eV Pu-238 154 at 83 eV Pu-241 2116 at 14.8 eV Am-243 13 at 1.35 eV Cm-242 288 at 30.2 eV Cm-243 1554 at 2.3 eV Cm-244 132 at 35 eV Cm-246 48 at 4.3 eV Cm-248 382 at 76 eV 17

For example, for U-235 the plot and data are as follows:

92-U-235(n, total fission) ENDF/B-VII.1 E = 0.0253 Sigma = 585.472 E = 19.301 Sigma = 673.898 18

Validation of Calculation of Atom Populations Results for atom populations from the equations and data described above were compared to those made using "Nuclear Analysis 1.0" computer code from Vilece Consulting. The Nuclear Analysis 1.0 computer code uses similar data and equations to those described above. To verify the computer code was working correctly, a reported case from the user manual was executed and compared to results for a test case from the equations presented above.

Nuclide t = 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> N (atoms)

Sr-92 2.24E+14 Reported case Mass = 45 mg Y-92 6.19E+13 Reported case Flux= 1.00E+13 cm-2 s-1 Decay, T = 7200 S Sr-92 2.24E+14 Test case Irrad, t = 7200 S Y-92 5.73E+13 Test case Fis Mat U235 The same example was then executed and compared for an irradiation time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> with decay time of 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />, or a total time of 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />.

Nuclide 2h 4h 6h 12h 16h 20h uCi uCi uCi uCi uCi uCi REPORTED CASE:

Sr-92 4.30E+05 2.58E+05 1.55E+05 3.33E+04 1.20E+04 4.30E+03 Y-92 9.1OE+04 1.66E+05 1.75E+05 1.OOE+05 5.60E+04 2.93E+04 TEST CASE:

Sr-92 4.30E+05 2.58E+05 1.55E+05 3.34E+04 1.20E+04 4.31E+03 Y-92 8.43E+04 1.64E+05 1.76E+05 1.01E+05 5.70E+04 2.98E+04 Error % -7.36E+00 -1.20E+00 5.71E-01 1.01 E+00 1.02E+00 1.02E+00 Note: e.g. 2h = t of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and T of 0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />, 16 h = t of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and T of 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br /> Results indicate good agreement. Additional comparisons of the calculations performed and those from Nuclear Analysis 1.0 are given later in this report.

19

RELEASED (Dispersed) ACTIVITY Activity at end of time of production, A(t), is given by:

A (t) = )N(t) where, t = time of production Decayed Activity, A(t + T) is given by:

A (t + T) = 2N(t + T)

Source dispersal fractions, D, are applied based on data given in ANSI/ANS 15-7 to estimate released (dispersed) activity to the reactor bay:

Accident or Form Environment Dispersal Fraction, D Gas Dry or 1 Halogen Fire or 1 Tritium (water vapor) Explosion 1 Particulate 1 Gas Wet, i.e. 1 Halogen in-pool 0.25 Tritium (water vapor) 0.25 Particulate 0 The dispersed and decayed activity, AD(t+T) is given by the following:

AD(t- -T)=A(t+T)*D 20

CONCENTRATION and TIME INTEGRATED EXPOSURE After the source is produced and decayed, the source is assumed to be removed from the experiment with all of the remaining activity instantaneously released to the reactor bay resulting in uniform airborne activity distribution throughout the entire reactor bay. The instantaneously released concentration, C(t+T), in the reactor bay is given by the following:

C(t+T) = AlOt+T) = OA_(t+T)

V 2 E9 ml where, V of 2 E9 ml is the reactor bay free air volume The time-integrated exposure and removal by radioactive decay and the ventilation system are taken into account as follows:

fQCt + 'd -~ C-,t + T)[1 k 1 -e(-k)]I where, k= + v and v is the confinement ventilation mode air removal rate constant v = 1.4 E-4 sl at a 600 cfm exhaust rate

-ris exposure time, ranging from 0 to r Time-integrated exposure in public areas is further reduced by removal of halogens and particulates by the confinement filters and by atmospheric dispersion. This gives the following equation for time-integrated exposure:

,uCi.h + T)(k)l (7 1 p~ -Q=+T

_C(t (1-ee )(I - R)(7.6 x 10-'))

ml k where, C(t+T) is in uCi/mI k is in 1/h T is exposure time in h R = 0.9 for halogens R = 0.9997 for particulates R = 0 for noble gases 7.6 E-3 is most limiting atmospheric dispersion parameter (i.e. X/Q) which was evaluated at a stack height of 30 m and a distance of 150 m and a receptor height of 30 m for Class F weather stability at a wind speed of 1 m/s. This X/Q value was presented and accepted in TS Amendment 17.

Exposure time is taken as 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for members of the public. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is sufficient time for the entire released activity to be vented from the reactor building (> 10 air changes).

21

For occupational workers an exposure time of 0.25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br /> is assumed to allow time for detection of the airborne release and evacuation from the reactor bay. No credit for respiratory protection is taken.

DOSE ASSESSMENT Dose to occupational workers and members of the public is determined as follows:

Dose = (Time-IntegratedExposure)(DCF) where, Dose is in rem = (uCi-h/ml) * (rem/h per uCi/ml)

DCF = Dose Conversion Factor in rem/h per uCi/ml taken from 10CFR20 Appendix B Effluent Concentrations (EC)

For halogens and particulates:

Effective DCF = (5 rem /2000 h) for workers [10CFR20Appendix B Table 1 air concentrationin uCi/ml]

Effective DCF = (0.05 rem / 8760 h) (2) for public [IOCFR20Appendix B Table 2 air concentration in uCi/ml]

For noble gases:

Effective DCF = (5 rem /2000 h) for workers [I OCFR20Appendix B Table 1 air concentrationin uCinml]

Effective DCF = (0.1 rem / 8 760 h) for public [IOCFR20Appendix B Table 2 air concentrationin uCi/ml]

For radioiodines:

Thyroid DCF (50 rem /2000 h) for workers [I OCFR20Appendix B Table I air concentration in uCi/ml]

DCF were based on limiting values given in 10CFR20 Appendix B. An age dependent factor of 2 is applied to the effective DCF for halogens and particulates to estimate the committed effective dose-equivalent to children.

Maximum effective dose-equivalents and thyroid dose-equivalent per fission per second (i.e. rem per f/s) were determined for each listed fissionable material for listed each irradiation time with no decay and with decay times up to 1 year for the assumed personnel and public exposure times.

Maximal doses may or may not correspond to maximal fission product inventories since dose conversion factors vary with the radionuclide based on the radiation decay characteristics, biological and metabolic characteristics, and physical half-life, i.e. dose varies as the fission product distribution changes over time. A decay period up to 1 year is realistic and accounts for the buildup and decay of fission product inventory from the decay of precursors.

22

EXTERNAL DOSE RATES External dose rates from gamma radiation release from fissionable materials is a function of mass, fluence rate, and time. For radiological control purposes, external dose rates from gamma radiation is limited by facility procedures consistent with experimental limitations and conditions and 10 CFR 20 requirements including ALARA practices.

EXPERIMENT LIMITS The postulated accident dose depends on the fission product activity present. Calculations were performed for numerous fissionable materials at a uniform fluence rate and a fixed mass for continuous irradiation times up to 1 year followed by decay times up to 1 year.

The design dose limits are 0.5 rem total effective dose-equivalent and 5 rem committed effective dose-equivalent to the thyroid for occupational workers. Dose to members of the public is limited to 0.01 rem (constraint dose) total effective dose-equivalent.

The limiting fission rate, f/s, is calculated as follows:

f/s = f Total fissions 1

• f Design dose limit I

[IrradiationTime] [Calculateddosefor irradiationconditions]

Results of the dose calculations were compared to determine the lowest fission rate for a given production time and decay time that is associated with the postulated accident doses. Data for thermal and non-thermal neutrons were compared and gave similar results. Therefore, both sets of data were combined to determine the minimal fission rates that satisfy the design dose limits. Dose limits are met for all fissionable materials in each of the two groups by use of the lowest fission rate.

The limiting fission rates were plotted against irradiation time. It is noteworthy that a change in the shape of the limiting fission rates occurs with irradiation time and depends on whether the sample is dry or wet. This is a result of the limiting condition being associated with public dose rather than occupational dose and the buildup of longer lived radionuclides with longer irradiation times. The dry sample results were determined to be more limiting. Wet samples were analyzed to determine the limiting fission rates prior to sample unloading, i.e. sample failure while still wet. Samples would be removed from a wet environment at the time of sample unloading making the dry sample conditions applicable. Therefore dry sample results are the limiting case for all samples.

23

Calculated Dry and Wet Sample Limiting Fission Rates vs. Irradiation Time:

Fueled Experiment Uniting Fission Rates 1-.0 E+13 1OrOE l l.1 + I II i

-*-U andRu

--- ANOthors i1.0O1E+09 1.0012-08 1,OOE.07 T 1OOE.OO 1.O0E-00 1.OOE+01 I0E0 1.00E.03 1.OOE-04 1.OOEn05 1.OOE.06 1.0OE+07 1.0OO=+08 Irradiation Time(s)

Irradiation Dry f/s Dry f/s Wet fls Seconds U, Pu Others All 1.OOE+01 2.67E+ 11 2.67E+1 1 1.56E+12 3.00E+01 9.79E+10 9.27E+10 6.16E+1 1 1.00E+02 3.82E+10 3.16E+10 2.74E+ 11 3.OOE+02 2.05E+10 1.14E+10 1.52E+ 11 1.OOE+03 1.03E+10 3.45E+09 1.07E+ 11 3.OOE+03 5.78E+09 1.23E+09 1.01 E+11 1.OOE+04 3.02E+09 4.24E+08 9.64E+10 3.00E+04 1.64E+09 1.84E+08 9.08E+10 1.OOE+05 9.25E+08 1.OOE+08 8.37E+10 3.OOE+05 6,93E+08 7.75E+07 6.87E+10 1.OOE+06 6.45E+08 7.43E+07 2.10E+10 3.OOE+06 6.07E+08 7.38E+07 6.09E+09 1.OOE+07 5.53E+08 7.29E+07 4.25E+09 3.OOE+07 4.86E+08 7.16E+07 4.19E+09 24

A trend line was determined by adjusting the intercept and slope of a multiple component power function for dry samples such that the limiting fission rate is never exceeded. This trend line is used to estimate the limiting fission rate, (f/s). The estimated limiting (f/s) values range from - 80% to a maximum of 100% of the calculated values with most being within 12%., i.e. the trend line was determined so that the fission rate limit is never exceeded at any time. The estimated line was used for irradiation times "t" from 10 s to 3.15E7 s (1y).

Estimated and Dry Sample Limiting Fission Rate (f/s) vs. Irradiation Time Trend Lines:

Fueled Experiment Urniting Fission Rates

-5 E61,mI. fm Al 0tms

...s- Esukmtetfm U ad N~

I a

I lOOE-O 1.00E+01 1.OOEr02 1.OOE+03 1.OOE.04 I.DOE.O5 1.0OE+06 1.OOE-07 1.0OE-08 frradwtion Tim*is)

Estimated to Irradiation Estimated Estimated Calculated Ratio time (s) f/s U and Pu f/s Others U and Pu Others 1.OOE+01 2.67E+1 1 2.66E+1 1 9.97E-01 9.98E-01 3.OOE+01 9.94E+10 9.07E+10 9.87E-01 9.78E-01 1.OOE+02 4.10E+10 2.79E+10 9.92E-01 8.84E-01 3.OOE+02 1.97E+10 9.56E+09 9.62E-01 8.39E-01 1.OOE+03 9.18E+09 2.99E+09 8.88E-01 8.65E-01 3.OOE+03 4.73E+09 1.06E+09 8.19E-01 8.65E-01 1.OOE+04 2.43E+09 3.74E+08 8.03E-01 8.83E-01 3.OOE+04 1.43E+09 1.72E+08 8.72E-01 9.33E-01 1.0OE+05 9.14E+08 9.93E+07 9.88E-01 9.88E-01 3.OOE+05 6.88E+08 7.74E+07 9.93E-01 1.OOE+00 1.OOE+06 5.67E+08 6.91 E+07 8.80E-01 9.30E-01 3.OOE+06 5.13E+08 6.62E+07 8.45E-01 8.96E-01 1.OOE+07 4.81 E+08 6.46E+07 8.71E-01 8.86E-01 3.OOE+07 4.65E+08 6.37E+07 9.57E-01 8.89E-01 25

Estimated trend line equation for isotopes of U and Pu:

(f / s) = 4.7E12[t-'7 ] + 7.7E1 1[t- 0 65 " ] + 5.4E8[t-001 ]

Estimated trend line equation for all other fissionable materials:

(f / s) = 2.54E12[t- 98 ] + 7.55E7[t-00 1]

Where, (f/s) is the limiting fission rate for irradiation time "t" "t" is in seconds and is limited to 3.15 E7 s (1 year)

For the purposes of Technical Specifications, the fission rate at 10 seconds applies to all irradiation times up to 10 seconds and the irradiation time is limited to 1 year.

MASS LIMITS For an incident uniform neutron fluence rate, the mass of the target may be determined from the limiting fission rate as follows:

M= (f / s)A P_(_NA where, M is fission material mass in g, (f/s) is the limiting fission rate for irradiation time "t" in seconds from the equation trend line for the applicable fissionable material given above, cm ,

c is the fission cross-section in p is neutron fluence rate in the units cm s ,

A is the fissionable material atomic mass in g per mole Which may also be written as:

M 1.66(f / s)A where, Yis the fission cross-section in barns 1.66 is the reciprocal of (1 E-24 cm2 / b)(6.022E23 atoms per mole)

Other factors may limit the mass to a lower value, such as license possession limits, a non-uniform incident neutron fluence rate in the experimental beam, reactivity and heat limits for experiments.

26

ENERGY RELEASE The energy release rate (RE) is calculated as follows:

RE = (200 MeV per fission)(cQvN) in MeV per second RE = (200 MeV per fission)(apN)(1 watt / 6.243 E12 MeV per s ), in watts Total energy release in Joules, J = (RE in watts)(Irradiation time in seconds)

In the equations above, atN is the fission rate and is limited as discussed previously. The energy release for the various irradiation times are therefore calculated at the limiting fission rates to give the following:

Energy Release Rate and Total Energy Release U ,, Pu Dry Sample for All Others Irradiation Irradiation Dry Sample for Dry Sample for U PU Dry Sample for All Others MeV/s Watts Joules MeV/s Watts Joules 1.00E+01 5.35E+13 8.57E+00 8.57E+01 5.33E+13 8.54E+00 8.54E+01 3.00E+01 1.85E+13 2.01E+13 3.23E+00 9.68E+01 6.31E+12 2.97E+00 8.91 E+ 0 1 1.00E+02 8.26E+12 1.32E+00 1.32E+02 1.01 E+00 1.01E+02 3.00E+02 2.28E+12 4.09E+12 6.56E-01 1.97E+02 6190E+1 1 3.65E-01 1.09E+02 1.00E+03 2.07E+12 3.31 E-01 3.31 E+02 1.11E-01 2.46E+1 1 1. 11 E+02 3.00E+03 1.16E+12 1.85E-01 5.55E+02 3.94E-02 1.18E+02 1.00E+04 8.47E+10 6.04E+11 9.68E-02 9.68E+02 1.36E-02 1.36E+02 3.00E+04 3.29E+ 11 5.27E-02 1.58E+03 3.69E+10 5.91 E-03 1.77E+02 1.00E+05 1.85E+ 11 2.96E-02 2.96E+03 2.01 E+1 0 3.22E-03 3.22E+02 3.00E+05 1.39E+ 11 2.22E-02 6.66E+03 1.55E+10 2.48E-03 7.45E+02 i .OOE+06 1.29E+11 2.07E-02 2.07E+04 1.49E+10 2.38E-03 2.38E+03 3.00E+06 1.48E+10 1.21E+11 1.94E-02 5.83E+04 1.46E+10 2.37E-03 7.1 OE+03 1.00E+07 1.11E+11 1.77E-02 1.77E+05 2.34E-03 2.34E+04 3.00E+07 1.43E+10 9.72E+10 1.56E-02 4.67E+05 I 2.29E-03 6.88E+04 3.OOE+07 The energy releases listed in the above table are based on the calculated limiting fission rates.

Energy would be the same or less than those listed above using equations for the estimated limiting fission rates.

The maximum energy release rate is 5.35 E13 MeV/s or 8.57 watts. This is a factor of approximately two times higher than the power permitted under TS Amendment 17 (8.57 W vs. 4.01 W).

27

Example Calculations Major steps for calculation of potential dose from a failed fueled experiment include the following:

1. Number of fission product atoms produced during irradiation (t)

2. Activity of fission products after production and decay (t + T)

3. Released activity and airborne concentrations of fission products in dry and wet experimental conditions

4. Filtration of fission products by the confinement system

5. Fission rate in the fissionable material potentially resulting in 10% of the occupational and public dose limits for the whole body and 10% of the occupational dose limits for the thyroid Calculations were made as described in this document using Microsoft Excel spreadsheets. A spreadsheet for each fissionable material and type of fission (thermal and non-thermal) were prepared. Illustrative descriptions of the above calculation steps are provided.

Due to the number of calculations made, example calculations will be presented for thermal fission of U-235. Comparison of calculations performed will be made to those using Nuclear Analysis 1.0 for fissionable materials and radionuclides that gave significant calculated doses. Independent verification of data entries used in this calculation was performed by the reactor staff. Also, comparison to the TS 3.8 Amendment 17 for U-235 is made.

Results of the calculations made are provided and summarized. The estimated minimal fission rate associated with the limiting dose for various irradiation and decay times are used for thermal and non-thermal fissions of the two groups of fissionable materials considered; (1) U and Pu and (2)

Other Fissionable Materials.

The example calculations for 1, 2, 3, and 4 above will be for the mass, A, of 133 from the thermal fission of 1 g of U-235 at a fluence rate of 1 E13 cm2 s 1. Decay chain data and U-235 fission yields are provided on the next page for A = 133. Note that there are 6 decay chains with 3 pathways leading to 1-133 production.

28

Decay Chains and Data for A = 133:

1. Sn-133 to Sb-133 to Te-133m to Te-133 to 1-133 to Xe-133m to Xe-133

2. Sn-133 to Sb-133 to Te-133m to Te-133 to 1-133 to Xe-133

3. Sn-133 to Sb-133 to Te-133m to 1-133 to Xe-133m to Xe-133

4. Sn-133 to Sb-133 to Te-133m to 1-133 to Xe-133

5. Sn-133 to Sb-133 to Te-133 to 1-133 to Xe-133n n to Xe-133

6. Sn-133 to Sb-133 to Te-133 to 1-133 to Xe-133 Yield per Decay Branching 100 fissions Constant Decay Nuclide Half-life (s) for U-235 (1/s) Fraction Sn133 1.44E+00 1.38E-01 4.81E-01 1 (B)

Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 (B,m)

Tel 33m 3.32E+03 2.99E+00 2.09E-04 0.175 (IT)

Tel 33 7.44E+02 1.15E+00 9.32E-04 1 (B) 1133 7.49E+04 1.65E-01 9.26E-06 0.0285 (B,m)

Xel33m 1.89E+05 1.89E-03 3.66E-06 1 (IT)

Xe133 4.53E+05 6.66E-04 1.53E-06 1 (B)

Sn133 1.44E+00 1.38E-01 4.81 E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 Tel 33m 3.32E+03 2.99E+00 2.09E-04 0.175 Tel 33 7.44E+02 1.15E+00 9.32E-04 1 1133 7.49E+04 1.65E-01 9.26E-06 0.9715 (B)

Xel 33 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 Tel33m 3.32E+03 2.99E+00 2.09E-04 0.825 (B) 1133 7.49E+04 1.65E-01 9.26E-06 0.0285 Xel33m 1.89E+05 1.89E-03 3.66E-06 1 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.1729 Tel33m 3.32E+03 2.99E+00 2.09E-04 0.825 1133 7.49E+04 1.65E-01 9.26E-06 0.9715 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81 E-01 1 Sb133 1.50E+02 2.26E+00 4.62E-03 0.8271 (B)

Tel 33 7.44E+02 1.15E+00 9.32E-04 1 1133 7.49E+04 1.65E-01 9.26E-06 0.0285 Xel33m 1.89E+05 1.89E-03 3.66E-06 1 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Sn133 1.44E+00 1.38E-01 4.81 E-01 Sb133 1.50E+02 2.26E+00 4.62E-03 0.8271 Tel 33 7.44E+02 1.15E+00 9.32E-04 1 1133 7.49E+04 1.65E-01 9.26E-06 0.9715 Xe133 4.53E+05 6.66E-04 1.53E-06 1 Where, (B) is beta minus decay, B,m) is beta minus decay to isomer, (IT) is isomeric transition 29

1. N(t) calculation results for mass (A) of 133 from the fission of 1 g of U-235 by a thermal fluence rate of 1 E13 cm"2 s-1 are as follows:

The 3 pathways leading to 1-133 are:

A: Sn-133 to Sb-133 toTe-133m to Te-133 to 1-133 B: Sn-133 to Sb-133 toTe-133mto 1-133 C: Sn-133 to Sb-133 to Te-133 to 1-133 N(t) evaluated at a production time, t, of 1.73 E5 seconds (or 2 days) gives:

N(1.73E5s) = 4.30 ElO atoms of Sn-133 N(1.73E5s) = 2.81E14 + 3.19E14 = 6.00 E14 atoms of Te-133 N(1.73E5s) = 2.45 E16 + 3.59 E16 + 4.04 E16 = 1.01 E17 atoms of 1-133 e.g. individual summations of precursors leading to 1-133 for time "t" of 1.73 E5 seconds are shown below:

A: Initial atoms of Sn-133 appearing as atoms of 1-133 +

Initial atoms of Sb-133 appearing as atoms of 1-133 +

Initial atoms of Te-133m appearing as atoms of 1-133 +

Initial atoms of Te- 133 appearing as atoms of 1-133 +

Initial atoms of 1-133 appearing as atoms of 1-133 =

5.32E+13

+8.71E+14

+6.66E+15

+1.48E+16 2.13E+15 Subtotal= 2.45 E16 B: Initial atoms of Sn- 133 appearing as atoms of 1-133 +

Initial atoms of Sb-133 appearing as atoms of 1-133 +

Initial atoms of Te-133m appearing as atoms of 1-133 =

2.51 E+14

+4.11E+15

+3.15E+16 Subtotal= 3.59 E16 Note that 1-133 contribution to itself is not added since it was included in pathway A C: Initial atoms of Sn-133 appearing as atoms of 1-133 +

Initial atoms of Sb- 133 appearing as atoms of 1-133 +

Initial atoms of Te-133 appearing as atoms of 1-133 =

1.47E+15

+2.41E+16

+1.48E+16 Subtotal = 4.04E16 Note that 1-133 contribution to itself is not added since it was included in pathway A 30

N(t) calculation results for mass (A) of 133 from the fission of 1 g of U-235 by a thermal fluence rate of I E13 cm"2 s-1 are as follows for t = 1.73E5 seconds:

N(1.73E5s) at end of production with no decay time from individual chain members Total Atoms

-Nuclide Atoms for All Chains Sn133 4.30E+10 4.48E+12 1.72E+13 6.72E+11 5.32E+13 1.18E+12 2.65E+11 4.30E+10 Sb133 7.33E+13 2.81E+14 1.10E+13 8.71E+14 1.93E+13 4.33E+12 7.78E+13 Te133m 2.15E+15 8.42E+13 6.66E+15 1.48E+14 3.33E+13 2.45E+15 Te133 1.85E+14 1.48E+16 3.37E+14 7.83E+13 6.OOE+14 1133 2.13E+15 4.88E+13 1.14E+13 1.01E+17 Xe133m 3.63E+13 1.16E+13 2.40E+15 Xe133 1.52E+13 9.22E+16 Sn133 4.30E+10 4.48E+12 1.72E+13 6.72E+11 5.32E+13 4.53E+13 Sb133 7.33E+13 2.81E+14 1.10E+13 8.71 E+14 7.42E+14 Te133m 2.15E+15 8.42E+13 6.66E+15 5.69E+15 Te133 1.85E+14 1.48E+16 1.30E+16 1133 2.13E+15 1.89E+15 Xe133 1.52E+13 Sn133 4.30E+10 4.48E+12 1.72E+13 2.51 E+14 5.59E+12 1.27E+12 Sb133 7.33E+13 2.81E+14 4.11E+15 9.16E+13 2.08E+13 Te133m 2.15E+15 3.15E+16 7.02E+14 1.59E+14 1133 2.13E+15 4.88E+13 1.14E+13 Xe133m 3.63E+13 1.16E+13 Xe133 1.52E+13 Sn133 4.30E+10 4.48E+12 1.72E+13 2.51 E+14 2.16E+14 Sb133 7.33E+13 2.81E+14 4.11E+15 3.53E+ 15 Te133m O.OOE+00 2.15E+15 3.15E+16 2.71 E+16 1133 O.OOE+00 O.OOE+00 2.13E+15 1.89E+15 Xe133 O.OOE+00 O.OOE+00 O.OOE+00 1.52E+13 Sn133 4.30E+10 4.48E+12 1.84E+13 1.47E+15 3.34E+13 7.75E+12 Sb133 7.33E+13 3.01E+14 2.41 E+16 5.47E+14 1.27E+14 Te133 1.85E+14 1.48E+16 3.37E+14 7.83E+13 1133 2.13E+15 4.88E+13 1.14E+13 Xe133m 3.63E+13 1.16E+13 Xe133 1.52E+13 Sn133 4.30E+10 4.48E+12 1.84E+13 1.47E+15 1.29E+15 Sb133 7.33E+13 3.01E+14 2.41 E+16 2.12E+16 Te133 1.85E+14 1.48E+16 1.30E+16 1133 2.13E+15 1.89E+15 Xe133 1.52E+13 31

The atom populations change for each pathway. Totals at time "t" are:

4.30 ElO atoms of Sn-133 6.00E14 atoms of Te-133 1.01 E17 atoms of 1-133 By comparison, Nuclear Analysis 1.0 results at time "t" are:

4.29E10 atoms of Sn-133 6.63E14 atoms of Te-133 8.79E 16 atoms of 1-133 Differences are - 12% or less and may be attributable to differences in half-lives, cross-sections, branching fractions from difference references. A comparison of the calculation to Nuclear Analysis 1.0 is made later.

32

2. A(t + T) calculation results for mass (A) of 133 from the fission of 1 g of U-235 by a thermal fluence rate of I E13 cm-2 s-1 follow for t = 1.73 E5 seconds and T = 3600 seconds are as follows:

e.g. 1-133 activity calculation:

N(t+T) = N(1.73E5 + 3600) =

1-133 produced from the decay of Sn- 133+Sb-133+Te- 133m+Te- 133+

the decay of 1-133 initially produced N(1.73E5 + 3600) = 4.82E+08+

8.72E+1 1+

1.70E+14+

5.65E+14+

9.75E+16=

9.82 E16 atoms A(t + T) = XN(t + T) = (9.26E-6/s)(9.82E16 atoms)(1 decay/atom)( 1 uCi / 3.7E4 dps)

= 2.46 E7 uCi of 1-133 For all nuclides with A = 133, A(t + T) activity in uCi are calculated to be:

Sn133 O.OOE+00 uCi Sb133 5.79E-01 uCi Tel 33m 6.55E+06 uCi Te133 1.90E+06 uCi 1133 2.46E+07 uCi Xel33m 2.44E+05 uCi Xe133 3.79E+06 uCi By comparison, Nuclear Analysis 1.0 gives the following activities:

Sb-133 8.05E-1 uCi Te-133m 5.79 E6 uCi Te-133 1.95 E6 uCi 1-133 2.13 E7uCi Xe-133 3.32 E6 uCi Results are within 20%.

33

N(1.73E5s. 3600s) at end of production with decay time from individual chain members Total Atoms Nuclide Atoms for All Chains Sn 133 0.00E+00 2.59E+03 3.67E+09 1.69E+08 4.82E+08 1.88E+05 6.87E+02 0.OOE+00 Sb133 4.64E+06 6.65E+12 3.06E+11 8.72E+ 11 3.40E+08 1.25E+06 4.64E+06 Tel33m 1.16E+15 5.40E+13 1.70E+14 7.10E+10 2.76E+08 1.16E+15 Te133 2.10E+13 5.65E+14 3.98E+ 11 2.13E+09 7.53E+13 1133 9.75E+16 9.35E+13 6.20E+1 1 9.82E+16 Xel33m 2.37E+15 3.14E+13 2.47E+15 Xe133 9.16E+16 9.17E+16 Sn 133 O.OE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Sb133 0.OOE+00 0.OOE+00 0.OOE+00 O.OOE+00 0.OOE+00 Tel33m 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Te133 0.OOE+00 0.OOE+00 0.OOE+00 1133 0.OOE+00 0.OOE+00 Xel33 2.13E+16 Sn133 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Sb133 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Tel33m 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 1133 3.47E+16 3.33E+13 2.21E+11 Xe133m 8.37E+14 1.11E+13 Xe133 2.03E+14 Sn133 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Sb133 O.OOE+00 0.OOE+00 O.00E+00 0.OOE+00 Tel 33m 0.OOE+00 0.OOE+00 0.OOE+00 1133 0.OOE+00 0.OOE+00 Xe133 3.25E+16 Sn133 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Sb133 0.OOE+00 0.OOE+00 O.00E+00 O.OOE+00 0.OOE+00 Tel 33 1.12E+13 3.01E+14 2.12E+11 1.13E+09 1133 3.91 E+16 3.75E+13 2.49E+ 11 Xel33m 9.54E+14 1.26E+13 Xe133 2.35E+14 Sn 133 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Sb133 0.OOE+00 0.OOE+00 0.OOE+00 0.OOE+00 Te133 0.OOE+00 0.OOE+00 0.OOE+00 1133 0.00E+00 0.OOE+00 Xe133 3.72E+16 34

3. Released activity and airborne concentrations of fission products in dry experimental conditions initially in the reactor bay C(t + T):

Initial concentration, C(t+T), in the reactor bay is given by the following:

C(t+T) = AD(t+T) / V=AD(t+T)/2 E9 ml where, V of 2 E9 ml is the estimated reactor bay free air volume (approximate)

D = 1 for dry samples For A of 133 produced by the fission of I g of U-235 by thermal neutrons at a fluence rate of 1 E13 cm -2 s-1 in the reactor bay are calculated to be as follows for t = 1.73E5 s and T = 3600 s:

Released Reactor Activity Bay To Bay Concentration uCi uCi/ml Sn133 0.OOE+00 0.00E+00 Sb133 5.79E-01 2.90E-10 Tel 33m 6.55E+06 3.27E-03 Te133 1.90E+06 9.48E-04 1133 2.46E+07 1.23E-02 Xel33m 2.44E+05 1.22E-04 Xe133 3.79E+06 1.90E-03 e.g reactor bay uCi/ml for 1-133:

C(t+T) = (2.46 E7 uCi / 2 E9 ml) = 1.23 E-2 uCi/ml For wet conditions, C(t+T) = 1.23E-2 uCi/ml * (0.25) = 3.08 E-3 uCi/ml 35

4. Effective and Thyroid Dose-Equivalent estimates for the reactor bay:

Time-integrated concentrations, uCi-h/ml, and dose conversion factors, DCF, and exposure time, z, are used to calculate personnel doses to personnel in the reactor bay.

Time-integrated exposure for the reactor bay is calculated as follows:

C(t + T)e(-k, 'dr'- C(t . k+ T) 11e(kT)]

where, k = X + v and v is the confinement ventilation mode air removal rate constant v = 1.4 E-4 s- or 0.51 h-1 at a 600 cfm confinement exhaust rate Tris 0.25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br /> for occupational workers Time-integrated exposure in public areas is further reduced by removal of halogens and particulates by the confinement filters and by atmospheric dispersion.

This gives the following equation for time-integrated exposure:

/,uCi h + T) -r-ml -

_C(t k- (1-e )(1- R)(7.6 x 10-3)

MI k where, C(t+T) is in uCi/ml v is 1.4 E-4 s1 or 0.51 h-1 at a 600 cfm confinement exhaust rate T is 24 h R = 0.9 for halogens R = 0.9997 for particulates R = 0 for noble gases 7.6 E-3 is most limiting atmospheric dispersion parameter (i.e. X/Q) which was evaluated at a height of 30 m (stack height) and a distance of 150 m (nearest building at a height of 30 m) for Class F weather stability at a wind speed of 1 m/s. This X/Q value was presented and accepted in TS Amendment 17.

Dose to occupational workers and members of the public is determined as follows:

Dose = (Time-IntegratedExposure)(DCF) where, Dose is in rem = (uCi-h/ml) * (rem/h per uCi/ml)

Dose Conversion Factor (DCF) is rem/h per uCi/ml taken from 10CFR20 Appendix B 36

For halogens and particulates:

Effective DCF = (5 rem / 2000 h) for workers [1 OCFR20 Appendix B Table I air concentration in uCi/ml]

Effective DCF = (0.05 rem / 8760 h)(2) for public [1 OCFR20 Appendix B Table 2 air concentration in uCi/ml]

For noble gases:

Effective DCF.= (5 rem / 2000 h) for workers [1 OCFR20 Appendix B Table 1 air concentration in uCi/ml]

Effective DCF = (0.1 rem / 8760 h) for public [1 OCFR20 Appendix B Table 2 air concentration in uCi/ml]

For radioiodines:

Thyroid DCF = (50 rem / 2000 h) for workers [1 OCFR20 Appendix B Table 1 air concentration in uCi/ml]

DCF were based on limiting values given in 10CFR20 Appendix B.

For-2A -1of 133 produced by the fission of 1 g of U-235 by thermal neutrons at a fluence rate of 1 E13 cm s doses in the reactor bay are calculated to be as follows for t = 1.73E5 s and T = 3600 s and t of 900 s (0.25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br />):

Dry Sample (example)

Te-133: Rem = [9.48E-4 uCi/ml *(1 - e"0 9 66 )

• 5 rem] = 1.52 E-2 rem (effective)

[3.86 per h* 2000 h

• 3E-5 uCi/ml ]

1-133: Rem = [1.23E-2 uCi/ml *(1 - e-0 .136 )

• 50 rem] = 7.18 E2 rem to thyroid

[ 0.543 per h* 2000 h

• 1 E-7 uCi/ml ]

Xe-133: Rem = [1.9E-3 uCi/mI *(I - e 0 . 2 9 )

• 5 rem ] = 1.11 E-2rem (effective)

[ 0.515 per h* 2000 h

• IE-4 uCi/ml]

Wet Sample (example)

Te-133 = 0 rem, since D for particulates is 0 Xe-133 has a D value of 1, so results are the same for wet and dry samples.

1-133 has a D value of 0.25 giving (718 rem)(0.25) = 180 rem 37

4. Effective Dose-Equivalent estimates form members of the public:

Time-integrated concentrations, uCi-h/ml, and dose conversion factors, DCF, exposure time, t, filter retention, and atmospheric dispersion are used to calculate doses to members of the public.

For-2A -1 of 133 produced by the fission of 1 g of U-235 by thermal neutrons at a fluence rate of 1 E13 cm s doses to the public are calculated to be as follows for t = 1.73E5 s and T = 3600 s and t of 8.64E4 s (24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />):

Dry Sample (example)

Te-133: Rem = [9.48E-4 uCi/ml *(1 - e'9 2 7 )'* 0.05 rem(2)] *(0.0003)(7.6E-3)= 8.0E-8 rem

[3.86 per h* 8760 h

• 8E-8 uCi/ml ]

1-133: Rem = rl.23E-2 uCi/mI *(I - e13°)

• 0.05 rem(2)1 *(0.1)(7.6E-3) = 2.0 E-1 rem

[0.543 per h* 8760 h

• 1 E-9 uCi/ml ]

Xe-133: Rem = rl.9E-3 uCi/ml *(1 - e"12. 4)

• 0.1 rem ] *(1)(7.6E-3) = 6.4 E-4 rem

[ 0.515 per h* 8760 h

• 5E-7 uCi/ml]

Wet Sample (example)

Te-133 = 0 rem, since D for particulates is 0 Xe-133 has a D value of 1, so results are the same for wet and dry samples.

1-133 has a D value of 0.25 giving (0.2 rem)(0.25) = 5.0 E-2 rem Bay Public DAC Thyroid EC Bay Bay Public Nuclide uCi-h/mi uCi-h/ml uCi/ml DAC uCilml uCi/ml Eff rem Thy rem Eff rem Sn133 O.OOE+00 O.OOE+00 1E-7 1E-9 O.OOE+00 O.OOE+00 Sb133 1.67E-11 3.85E-17 1E-7 1E-9 4.17E-07 4.40E-13 Tel33m 7.02E-04 5.92E-09 4.E-06 2.E-06 2.E-08 4.21E-01 8.78E+00 3.38E-06 Te133 1.52E-04 5.59E-10 3.E-05 9.E-06 8.E-08 1.52E-02 4.22E-01 7.98E-08 1133 2.87E-03 1.72E-05 4.E-07 1.E-07 1.E-09 1.92E+01 7.18E+02 1.96E-01 Xel33m 2.87E-05 1.78E-06 1.E-04 6.E-07 7.17E-04 3.38E-05 Xe133 4.45E-04 2.80E-05 1.E-04 5.E-07 1.11E-02 6.39E-04 38

Calculated doses for workers and the public for all fission products from the fission of 1 g of U-235 by thermal neutrons at a fluence rate of I E13 cm"2 s" for t = 1.73E5 s and T = 3600 s are:

Dry Eff Thy PUB Eff Environment Rem Rem Rem All Noble Gas 9.70E+00 3.27E-01 All Bromines 7.46E-02 3.23E-04 All lodines 3.85E+01 1.54E+03 3.78E-01 All Particulates 5.61 E+02 6.33E-03 Total 6.09E+02 1.54E+03 7.11E-01 Wet Eff Thy PUB Eff Environment Rem Rem Rem All Noble Gas 9.70E+00 3.27E-01 All Bromines 1.87E-02 8.08E-05 All lodines 9.62E+00 3.35E+02 9.45E-02 Total 1.94E+01 3.35E+02 4.21E-01 39

5. Fission rate (f/s) associated with dose limits:

Limiting fission rate, f/s, is then calculated as follows:

f/s = [ Total fissions I

• f Design dose limit 1

[Irradiation Time] [Calculated dose for irradiation conditions]

e.g. Thermal fission of U-235 at 1.0 E5 s for a dry sample:

f/s = [Of fl * [0.5 rem] = E3,9.based effective dose-equivalent I s] [1.4E3 rem] to occupational personnel For the fission of 1 g of U-235 by thermal neutrons at a fluence rate of 1 E13 cm"-2s" , doses and f/s are calculated for times from t = 1Os to t = 3E7s:

Dry Rem Dry Rem Dry Rem Wet RemnI Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Pub WB Bay WB Bay Thy Pub WB Seconds Fissions 2.28E+01 1.49E-01 1.12E-02 2.90E+0 )0 1.80E-02 1.10E-02 1.OOE+01 1.50E+14 6.21E+01 4.53E-01 2.87E-02 7.70E+O0 5.48E-02 2.82E-02 3.OOE+01 4.50E+14 1.58E+02 1.55E+00 7.02E-02 1.98E+O 1 1.91E-01 6.87E-02 1.OOE+02 1.50E+15 3.02E+02 4.90E+00 1.34E-01 3.66E+0 1 6.29E-01 1.31 E-01 3.OOE+02 4.50E+15 5.20E+02 1.78E+01 2.03E-01 5.21 E+0 1 2.43E+00 1.99E-01 1.OOE+03 1.50E+16 7.97E+02 5.72E+01 2.46E-01 5.51 E+0 1 8.49E+00 2.36E-01 3.OOE+03 4.50E+16 1.09E+03 1.83E+02 3.33E-01 5.75E+O 1 3.30E+01 3.OOE-01 1.OOE+04 1.50E+17 1.23E+03 4.77E+02 4.75E-01 6.13E+0 1 9.87E+01 3.87E-01 3.OOE+04 4.50E+17 1.16E+03 7.41 E-01 6.84E+0 1 2.50E+02 5.23E-01 1.59E+03 2.13E+03 1.38E+00 8.76E+0 1 4.55E+02 9.85E-01 3.OOE+05 4.50E+18 1.97E+03 3.57E+03 4.91 E+00 2.05E+0 2 7.68E+02 4.25E+00 1.OOE+06 1.50E+19 2.84E+03 4.70E+03 1.48E+01 5.43E+0 2 1.04E+03 1.39E+01 3.OOE+06 4.50E+19 4.34E+03 5.24E+03 2.08E+01 7.47E+0 2 1.18E+03 1.97E+01 1.OOE+07 1.50E+20 6.44E+03 6.21 E+03 2.11E+01 7.57E+0 2 1.42E+03 1.99E+01 3.OOE+07 4.50E+20 Dry fVs Dry fUs Dry fUs WET fUs WET fVs \NET fs Irradiation WB Thy Pub WB Thy FPub S econds 3.29E+ 11 5.03E+14 1.34E+13 2.58E+12 4.16E+15 1I.36E+13 1.OOE+01 1.21E+11 1.65E+14 5.22E+12 9.73E+ 11 1.37E+15 I5.32E+12 3.OOE+01 4.74E+10 4.84E+13 2.14E+12 3.79E+ 11 3.92E+14 e2.18E+12 1.OOE+02 2.48E+10 1.53E+13 1.12E+12 2.05E+ 11 1.19E+14 11.14E+12 3.OOE+02 1.44E+10 4.21E+12 7.38E+1 1 1.44E+ 11 3.08E+13 7 .53E+1 1 1.OOE+03 9.40E+09 1.31E+12 6.09E+ 11 1.36E+11 8.83E+12 6 .35E+1 1 3.OOE+03 6.88E+09 4.1OE+11 4.50E+ 11 1.30E+ 11 2.27E+12 5 .00E+11 1.OOE+04 6.09E+09 1.57E+11 3.16E+ 11 1.22E+ 11 7.59E+11 3 .87E+11 3.OOE+04 6.46E+10 2.02 E+11 1.10E+11 3.OOE+11 2 .87E+1 1 4.71 E+09 3.52E+10 1.09E+11 8.56E+10 1.65E+11 1.52E+1 1 3.OOE+05 3.80E+09 2.10E+10 3.05E+10 3.66E+10 9.76E+10 3 .53E+10 1.OOE+06 2.64E+09 1.59E+10 1.01 E+10 1.38E+10 7.21E+10 1 .08E+10 3.OOE+06 1.73E+09 1.43E+10 7.21E+09 1.OOE+10 6.35E+10 7'.61E+09 1.OOE+07 1.16E+09 1.21E+10 7.10E+09 9.90E+09 5.28E+10 7'.53E+09 3.00E+07 40

DETAILED CALCULATION RESULTS FOR THE THERMAL FISSION OF U-235 Fissionable material: U-235 Fission: Thermal Mass: Ig Irradiation time, t: 100 s Decay time, T: Os and 300 s Cross-section: 585 b Neutron fluence rate: I El3 cm "2s-l Using the above data and assumptions given previously for this calculation, this case was executed using a Microsoft Excel spreadsheet as described previously. Results and detailed calculation results are given below and on the following pages.

Summary of dose results:

t=100 s, T=300s Dry WB THY PUB WB Source Filter Environment Rem Rem Rem Release Release All Noble Gas 4.58E+00 1.85E-02 1 1 Noble Gases All Bromines 4.79E-01 1.74E-04 1 0.1 Bromines All lodines 2.91 E-02 1.55E+00 1..99E-04 1 0.1 lodines All Particulates 3.53E+01 5.50E-05 1 0.0003 Particulates Total 4.04E+01 1.55E+00 1.89E-02 Wet WB THY PUB WB Dispersal Filter Environment Rem Rem Rem Release Release All Noble Gas 4.58E+00 1.85E-02 1 1 Noble Gases All Bromines 1.20E-01 4.36E-05 0.25 0.1 Bromines All lodines 7.27E-03 1.69E-01 4.97E-05 0.25 0.1 lodines Total 4.71 E+00 1.69E-01 1.86E-02 0 Particulates t =100 s, T=0s Dry WB THY PUB WB Environment Rem Rem Rem All Noble Gas 1.87E+01 6.83E-02 All Bromines 4.55E+00 1.59E-03 All lodines 2.41 E-02 1.43E+00 1.63E-04 All Particulates 1.34E+02 1.62E-04 Total 1.58E+02 1.43E+00 7.02E-02 Wet WB THY PUB WB Environment Rem Rem Rem All Noble Gas 1.87E+01 6.83E-02 All Bromines 1.14E+00 3.97E-04 All lodines 6.02E-03 1.39E-01 4.06E-05 Total 1.98E+01 1.39E-01 6.87E-02 41

Fission rate calculation results for all decay times (0 to 1 y):

Minimum Minimum Dry Wet Irradiati on Total Sample Sample Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Second!s Fissions f/s f/s w

Bay WB Bay Thy Pub WB Bay WB Bay Thy Pub WB 1.OOE+02 1.50E+15 4.74E+10 3.79E+11 .1.58E+02 1.55E+00 7.02E-02 1.98E+01 1.91E-01 6.87E-02 Dry f/s Dry f/s Dry f/s WET f/s WET f/s WET f/s Irradiation WB Thy Pub WB Thy Pub Seconds 4.74E+10 4.84E+13 2.14E+12 3.79E+11 3.92E+14 2.18E+12 1.OOE+02 The WB (whole body or effective dose-equivalent) results are highest at T = 0 s while the Thyroid effective dose-equivalent are highest at T = 300 s for a dry sample in the reactor bay and T = 3500 s for a wet sample in the reactor bay. The highest dose values for decay times from 0 s to 1 y are shown.

The WB dose for occupational workers in the reactor bay give the limiting (minimal) fission rate for the data and assumptions made in the calculation for both dry and wet samples.

A detailed summary of calculation results for fission products for and irradiation time (t) of 100 s and a decay time (T) of 0 s and 300 s are given on the following pages.

Notes:

" Doses were calculated and summed first without taking filter retention and release (dispersal) into account. Then the applicable dispersal factor and filter retention factors were applied to the summed data. Filter release fraction = I - R, where R is filter retention. The filter release applies only to public dose. R = 0 for noble gaees. 0.9 for halogens, and 0.9997 for particulates.

" For dry samples, some nuclides of Te and Sb have DAC values based on the thyroid dose.

Te and Sb are particulates, so these nuclides have a dispersal factor of 0 for wet samples.

" Dispersal factor for wet samples are used to modify the respective dry sample doses to obtain the wet sample doses, e.g. for iodines with a dispersal factor of 0.25.

42

Initial Decay Bay Bay Unfiltered WB Public Activity Released dose Thy dose WB Activity Nuclide uCi uCi rem rem rem Kr83m 4.26E+01 5.40E+02 1.52E-08 2.66E-10 Kr85m 4.44E+03 1.53E+04 2.21E-04 5.OOE-06 Kr85 2.14E-02 2.28E-02 6.69E-11 1.39E-12 Kr87 1.20E+05 1.83E+05 1.OOE-02 1.88E-04 Kr88 1.11E+05 1.19E+05 1.69E-02 3.79E-04 Kr89 5.54E+06 1.87E+06 1.65E+00 2.96E-03 Kr90 1.89E+07 3.03E+04 4.88E-03 8.46E-06 Kr9l 1.36E+07 4.29E-04 1.85E-11 3.20E-14 Kr92 6.81E+06 5.66E-43 5.22E-51 9.05E-54 Kr93 1.98E+06 1.95E-64 1.26E-72 2.18E-75 Kr94 3.52E+05 O.OOE+00 O.OOE+00 O.OOE+00 Kr95 2.91E+04 4.83E-112 1.89E-120 3.27E-123 Kr96 1.53E+05 O.OOE+00 O.OOE+00 O.OOE+00 Kr97 1.20E+02 O.OOE+00 O.OOE+00 O.OOE+00 Xel31 rm 9.95E-05 1.20E-04 3.53E-07 5.09E-09 Xel33m 2.82E+00 2.87E+00 8.41E-09 1.99E-10 Xe133 5.78E-01 5.79E-01 1.70E-09 4.87E-11 Xel35m 1.06E+05 8.90E+04 2.12E-03 1.50E-05 Xe135 2.90E+03 3.49E+03 1.02E-04 1.85E-06 Xe137 5.40E+06 2.70E+06 2.79E+00 5.15E-03 Xe138 1.96E+06 1.57E+06 8.21E-02 4.92E-04 Xe139 1.68E+07 9.01E+04 1.78E-02 3.08E-05 Xe140 1.47E+07 3.37E+00 2.29E-07 3.97E-10 Xe141 5.08E+06 1.60E-46 1.38E-54 2.39E-57 Xe142 1.78E+06 1.68E-68 1.03E-76 1.79E-79 Xe143 2.15E+05 2.OOE-296 3.01E-305 0.OOE+00 Xe144 2.45E+04 1.35E-71 8.14E-80 1.41E-82 Xe145 2.90E+02 0.00E+00 O.OOE+00 0.OOE+00 Te131 2.59E+04 2.25E+04 1.30E-03 2.72E-02 1.12E-05 Sb131 4.05E+05 4.40E+05 6.27E-03 1.04E-01 6.87E-05 Tel31m 6.24E+02 6.92EE+02 5.40E-04 1.01 E-02 2.82E-05 Te132 1.76E+03 2.72E+03 3.18E-03 8.84E-02 1.26E-04 Te133m 2.57E+05 2.62E+05 1.68E-02 3.51E-01 2.25E-04 Te133 5.61E+05 4.35E+05 3.49E-03 9.69E-02 3.05E-05 Te134 8.10E+05 7.47E+05 9.34E-03 1.95E-01 1.54E-04 1-129 3.03E-05 3.16E-04 7.41E-09 2.32E-07 3.36E-10 1131 5.71E+00 1.30E+01 4.56E-05 1.90E-03 2.74E-06 1132 6.33E+02 6.75E+02 4.58E-05 6.36E-04 9.01E-07 1133 1.15E+03 2.52E+03 1.97E-03 7.37E-02 1.01E-04 1134 9.74E+04 1.41E+05 1.88E-03 3.91E-05 1135 1.26E+05 1.45E+05 2.52E-02 5.99E-01 8.51E-04 Br83 7.44E+03 1.98E+04 1.87E-04 5.97E-06 Br84 6.38E+04 1.16E+05 1.46E-03 1.73E-05 Br84m 1.19E+04 6.65E+03 9.43E-03 1.94E-05 Br85 1.14E+06 4.76E+05 3.87E-01 6.88E-04 Br86 4.85E+06 1.45E+05 3.97E-02 6.90E-05 Br87 5.79E+06 1.49E+05 4.12E-02 7.14E-05 Br88 6.62E+06 2.10E+01 1.72E-06 2.98E-09 Br89 4.40E+06 1.32E-14 2.90E-22 5.04E-25 Br9O 2.24E+06 6.60E-42 6.28E-50 1.09E-52 Br91 9.10E+05 5.26E-162 1.42E-170 2.47E-1 73 Br92 1.09E+05 2.64E-261 4.49E-270 7.79E-273 Br93 1.25E+04 0.OOE+00 0.OOE+00 0.OOE+00 Br96 7.74E+00 0.OOE+00 0.OOE+00 0.OOE+00 43

DOSE RESULTS Calculated doses for the assumed conditions and a mass of 1g at a neutron fluence rate of 1 E13 cm 2s' are given below for commonly used fissionable materials and those that were determined to be limiting. The total number of fissions varies based on the fission reaction cross-section.

Thermal Fission of U-235 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Pub WB Bay WB Bay Thy Pub WB Seconds Fissions 2.28E+01 1.49E-01 1.12E-02 2.90E+00 1.80E-02 1.10E-02 1.OOE+01 1.50E+14 6.21 E+01 4.53E-01 2.87E-02 7.70E+00 5.48E-02 2.82E-02 3.OOE+01 4.50E+14 1.58E+02 1.55E+00 7.02 E-02 1.98E+01 1.91 E-01 6.87E-02 1.OOE+02 1.50E+15 3.02E+02 4.90E+00 1.34E-01 3.66E+01 6.29E-01 1.31 E-01 3.00E+02 4.50E+15 5.20E+02 1.78E+01 2.04E-01 5.21E+01 2.43E+00 1.99E-01 1.OOE+03 1.50E+16 7.97E+02 5.72E+01 2.46E-01 5.51 E+01 8.49E+00 2.36E-01 3.OOE+03 4.50E+16 1.09E+03 1.83E+02 3.34E-01 5.75E+01 3.30E+01 3.OOE-01 1.OOE+04 1.50E+17 1.23E+03 4.77E+02 4.79E-01 6.13E+01 9.87E+01 3.87E-01 3.OOE+04 4.50E+17 1.40E+03 1.16E+03 7.44E-01 6.84E+01 2.50E+02 5.23E-01 1.OOE+05 1.50E+18 1.59E+03 2.13E+03 1.38E+00 8.76E+01 4.55E+02 9.85E-01 3.OOE+05 4.50E+18 1.97E+03 3.57E+03 4.92E+00 2.05E+02 7.68E+02 4.25E+00 1.00E+06 1.50E+19 2.84E+03 4.70E+03 1.48E+01 5.43E+02 1.04E+03 1.39E+01 3.00E+06 4.50E+19 4.34E+03 5.24E+03 2.08E+01 7.48E+02 1.18E+03 1.97E+01 1.OOE+07 1.50E+20 6.44E+03 6.21 E+03 2.12E+01 7.57E+02 1.42E+03 1.99E+01 3.OOE+07 4.50E+20 Fast Fission of U-238 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Bay WB Bay Thy Pub WB Seconds Fissions 7.57E-04 3.67E-06 2.54E-07 7.40E-05 4.54E-07 2.49E-07 1.OOE+01 4.05E+09 2.01 E-03 1.12E-05 6.43E-07 1.86E-04 1.40E-06 6.30E-07 3.OOE+01 1.211E+10 4.90E-03 3.86E-05 1.57E-06 4.45E-04 4.97E-06 1.53E-06 1.OOE+02 4.05E+10 9.21 E-03 1.24E-05 3.01 E-06 8.28E-04 1.69E-05 2.95E-06 3.OOE+02 1.21E+11 1.57E-02 4.69E-04 4.60E-06 1.19E-03 6.71 E-05 4.47E-06 1.OOE+03 4.05E+ 11 2.28E-02 1.53E-03 5.46E-06 1.26E-03 2.32E-04 5.18E-06 3.OOE+03 1.211E+12 3.03E-02 4.88E-03 7.22E-06 1.31E-03 8.74E-04 6.33E-06 1.OOE+04 4.05E+12 3.62E-02 1.25E-02 1.04E-05 1.39E-03 2.57E-03 8.03E-06 3.OOE+04 1.21E+13 4.44E-02 3.01 E-02 1.70E-05 1.57E-03 6.41 E-03 1.131E-05 1.OOE+05 4.05E+13 5.12E-02 5.49E-02 3.24E-05 2.03E-03 1.15E-02 2.22E-05 3.OOE+05 1.21E+14 5.99E-02 8.99E-02 1.14E-04 4.73E-03 1.80E-02 9.73E-05 1.OOE+06 4.05E+14 7.85E-02 1.19E-01 3.39E-04 1.24E-02 2.58E-02 3.16E-04 3.OOE+06 1.21E+15 1.09E-01 1.42E-01 4.78E-04 1.71 E-02 3.16E-02 4.49E-04 1.OOE+07 4.05E+15 1.54E-01 1.91 E-01 4.95E-04 1.76E-02 4.40E-02 4.54E-04 3.OOE+07 1.21E+16 44

DOSE RESULTS Calculated doses for the assumed conditions and a mass of 1g at a neutron fluence rate of 1 E 13 cm 2s l are given below for commonly used fissionable materials and those that were determined to be limiting. The total number of fissions varies based on the fission reaction cross-section.

Thermal Fission of Pu-239 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Bay WB Bay Thy Pub WB Seconds Fissions 2.51E+01 2.19E-01 7.OOE-03 1.97E+00 2.94E-02 6.88E-03 1.OOE+01 1.89E+14 6.79E+01 6.62E-01 1.92E-02 5.35E+00 8.90E-02 1.88E-02 3.OOE+01 5.68E+14 1.73E+02 2.24E+00 5.20E-02 1.41E+01 3.04E-01 5.10E-02 1.OOE+02 1.89E+15 3.47E+02 7.OOE+00 1.09E-01 2.89E+01 9.65E-01 1.06E-01 3.OOE+02 5.68E+15 6.41 E+02 2.52E+01 1.74E-01 4.36E+01 3.60E+00 1.68E-01 1.00E+03 1.89E+16 1.04E+03 8.09E+01 2.10E-01 4.66E+01 1.25E+01 1.96E-01 3.OOE+03 5.68E+16 1.60E+03 2.64E+02 2.87E-01 4.88E+01 4.81 E+01 2.38E-01 1.OOE+04 1.89E+17 2.26E+03 7.03E+02 4.51E-01 5.31E+01 1.45E+02 3.13E-01 3.OOE+04 5.68E+17 3.30E+03 1.77E+03 8.58E-01 6.39E+01 3.77E+02 5.16E-01 1.00E+05 1.89E+18 4.15E+03 3.48E+03 2.04E+00 9.93E+01 7.36E+02 1.38E+00 3.00E+05 5.68E+18 4.78E+03 6.35E+03 9.07E+00 3.33E+02 1.38E+03 7.85E+00 1.OOE+06 1.89E+19 6.00E+03 8.87E+03 2.91E+01 1.02E+03 1.99E+03 2.73E+01 3.OOE+06 5.68E+19 7.68E+03 1.08E+04 4.15E+01 1.44E+03 2.47E+03 3.93E+01 1.OOE+07 1.89E+20 9.88E+03 1.48E+04 4.28E+01 1.48E+03 3.48E+03 3.97E+01 3.00E+07 5.68E+20 Thermal Fission of U-233 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Bay WB Bay Thy Pub WB Seconds Fissions 1.61 E+01 1.39E-01 8.74E-03 2.51E+00 1.63E-02 8.55E-03 1.OOE+01 1.37E+14 4.44E+01 4.19E-01 2.34E-02 6.69E+00 4.92E-02 2.28E-02 3.OOE+01 4.12E+14 1.16E+02 .1.42E+00 6.07E-02 1.71E+01 1.68E-01 5.90E-02 1.OOE+02 1.37E+15 2.26E+02 4.40E+00 1.22E-01 3.32E+01 5.33E-01 1.18E-01 3.OOE+02 4.12E+15 3.92E+02 1.56E+01 1.90E-01 4.83E+01 2.01 E+00 1.85E-01 1.OOE+03 1.37E+16 6.03E+02 4.94E+01 2.37E-01 5.13E+01 7.09E+00 2.26E-01 3.OOE+03 4.12E+16 8.41 E+02 1.61E+02 3.34E-01 5.38E+01 2.81E+01 3.04E-01 1.OOE+04 1.37E+17 9.59E+02 4.31 E+02 4.85E-01 5.76E+01 8.63E+01 4.04E-01 3.00E+04 4.12E+17 1.12E+03 1.1 IE+03 7.55E-01 6.48E+01 2.31 E+02 5.50E-01 1.OOE+05 1.37E+18 1.31 E+03 2.25E+03 1.55E+00 8.87E+01 4.69E+02 1.13E+00 3.OOE+05 4.12E+18 1.72E+03 4.28E+03 6.46E+00 2.52E+02 9.23E+02 5.65E+00 1.OOE+06 1.37E+19 2.70E+03 6.12E+03 2.06E+01 7.36E+02 1.37E+03 1.94E+01 3.OOE+06 4.12E+19 4.15E+03 7.77E+03 2.95E+01 1.04E+03 1.77E+03 2.79E+01 1.OOE+07 1.37E+20 5.98E+03 1.11 E+04 3.06E+01 1.07E+03 2.62E+03 2.82E+01 3.OOE+07 4.12E+20 45

DOSE RESULTS Calculated doses for the assumed conditions and a mass of 1g at a neutron fluence rate of 1 El 3 cm-2s1 are given below for commonly used fissionable materials and those that were determined to be limiting. The total number of fissions varies based on the fission reaction cross-section.

Thermal Fission of Cf-249 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Bay WB Bay Thy Pub WB Seconds Fissions 6.66E+01 3.16E-01 8.90E-03 2.41E+00 4.58E-02 8.61 E-03 1.OOE+01 4.06E+14 1.94E+02 9.55E-01 2.47E-02 6.62E+00 1.38E-01 2.38E-02 3.OOE+01 1.22E+15 5.92E+02 3.23E+00 6.87E-02 1.80E+01 4.68E-01 6.55E-02 1.OOE+02 4.06E+15 1.72E+03 9.94E+00 1.49E-01 3.72E+01 1.46E+00 1.39E-01 3.00E+02 1.22E+16 5.80E+03 3.52E+01 2.62E-01 5.69E+01 5.30E+00 2.22E-01 1.OOE+03 4.06E+16 1.65E+04 1.11E+02 3.85E-01 6.10E+01 1.80E+01 2.58E-01 3.OOE+03 1.22E+17 4.79E+04 3.67E+02 7.20E-01 6.41 E+01 6.81 E+01 3.19E-01 1.OOE+04 4.06E+17 1.10E+05 9.96E+02 1.44E+00 7.14E+01 2.04E+02 4.60E-01 3.OOE+04 1.22E+18 1.97E+05 2.60E+03 2.90E+00 9.39E+01 5.46E+02 9.53E-01 1.OOE+05 4.06E+18 2.50E+05 5.34E+03 6.08E+00 1.81 E+02 1.12E+03 3.21 E+00 3.OOE+05 1.22E+19 2.61 E+05 1.04E+04 2.32E+01 7.54E+02 2.27E+03 1.93E+01 1.OOE+06 4.06E+19 2.63E+05 1.55E+04 7.16E+01 2.41E+03 3.53E+03 6.66E+01 3.OOE+06 1.22E+20 2.67E+05 2.22E+04 1.02E+02 3.45E+03 5.19E+03 9.54E+01 1.OOE+07 4.06E+20 2.72E+05 3.78E+04 1.07E+02 3.58E+03 9.09E+03 9.69E+01 3.OOE+07 1.22E+21 Fast Fission of Cm-248 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Bay WB Bay Thy Pub WB Seconds Fissions 1.74E+00 4.67E-03 4.07E-04 1.15E-01 6.81E-04 4.02E-04 1.00E+01 9.28E+12 4.92E+00 1.42E-02 1.06E-03 2.94E-01 2.07E-03 1.04E-03 3.OOE+01 2.78E+13 1.34E+01 4.90E-02 2.70E-03 7.33E-01 7.20E-03 2.65E-03 1.OOE+02 9.28E+13 3.23E+01 1.56E-01 5.43E-03 1.42E+00 2.35E-02 5.27E-03 3.OOE+02 2.78E+14 8.95E+01 5.73E-01 8.71 E-03 2.11E+00 8.89E-02 8.12E-03 1.00E+03 9.28E+14 2.25E+02 1.83E+00 1.1OE-02 2.24E+00 2.97E-01 9.10E-03 3.OOE+03 2.78E+15 6.08E+02 5.77E+00 1.62E-02 2.29E+00 1.08E+00 1.01 E-02 1.OOE+04 9.28E+15 1.37E+03 1.46E+01 2.75E-02 2.38E+00 3.10E+00 1.22E-02 3.OOE+04 2.78E+16 2.53E+03 3.40E+01 4.90E-02 2.59E+00 7.41E+00 1.73E-02 1.OOE+05 9.28E+16 3.32E+03 6.09E+01 7.99E-02 3.13E+00 1.31E+01 3.21 E-02 3.OOE+05 2.78E+17 3.47E+03 1.02E+02 1.90E-01 6.39E+00 2.20E+01 1.25E-01 1.OOE+06 9.28E+17 3.51 E+03 1.38E+02 4.72E-01 1.57E+01 3.08E+01 3.92E-01 3.OOE+06 2.78E+18 3.58E+03 1.72E+02 6.52E-01 2.14E+01 3.94E+01 5.55E-01 1.OOE+07 9.28E+18 3.71 E+03 2.47E+02 7.01 E-01 2.21E+01 5.82E+01 5.68E-01 3.OOE+07 2.78E+19 46

DOSE RESULTS Calculated doses for the assumed conditions and a mass of Ig at a neutron fluence rate of 1 E 13 cm 2s-I are given below for commonly used fissionable materials and those that were determined to be limiting. The total number of fissions varies based on the fission reaction cross-section.

Thermal Fission of Cf-251 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Bay WB Bay Thy Pub WB Seconds Fissions 2.21 E+02 7.16E-01 3.31E-02 9.10E+00 9.31 E-02 3.25E-02 1.OOE+01 1.19E+15 6.40E+02 2.17E+00 9.12E-02 2.47E+01 2.83E-01 8.92E-02 3.OOE+01 3.56E+15 1.88E+03 7.46E+00 2.54E-01 6.72E+01 9.87E-01 2.47E-01 1.OOE+02 1.19E+16 5.21 E+03 2.37E+01 5.46E-01 1.39E+02 3.24E+00 5.20E-01 3.OOE+02 3.56E+16 1.72E+04 8.68E+01 9.31E-01 2.13E+02 1.24E+01 8.20E-01 1.OOE+03 1.19E+17 4.81 E+04 2.79E+02 1.26E+00 2.27E+02 4.26E+01 9.10E-01 3.00E+03 3.56E+17 1.39E+05 8.94E+02 2.11E+00 2.33E+02 1.62E+02 9.81 E-01 1.OOE+04 1.19E+18 3.21 E+05 2.33E+03 3.93E+00 2.45E+02 4.80E+02 1.15E+00 3.OOE+04 3.56E+18 5.91 E+05 5.66E+03 7.25E+00 2.79E+02 1.21E+03 1.75E+00 1.O0E+05 1.19E+19 7.66E+05 1.06E+04 1.19E+01 3.75E+02 2.23E+03 4.09E+00 3.OOE+05 3.56E+19 7.99E+05 1.83E+04 3.01E+01 9.71E+02 3.90E+03 2.06E+01 1.OOE+06 1.19E+20 8.04E+05 2.52E+04 8.04E+01 2.69E+03 5.58E+03 6.93E+01 3.O0E+06 3.56E+20 8.14E+05 3.22E+04 1.12E+02 3.75E+03 7.34E+03 9.90E+01 1.OOE+07 1.19E+21 8.29E+05 4.80E+04 1.17E+02 3.89E+03 1.13E+04 1.01 E+02 3.OOE+07 3.56E+21 Thermal Fission of Am-242 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy PubWB Bay WB Bay Thy Pub WB Seconds Fissions 7.62E+01 5.OOE-01 1.72E-02 4.62E+00 6.40E-02 1.69E-02 1.OOE+01 5.24E+14 2.08E+02 1.51 E+00 4.74E-02 1.32E+01 1.94E-01 4.65E-02 3.OOE+01 1.57E+15 5.45E+02 5.16E+00 1.30E-01 3.55E+01 6.66E-01 1.28E-01 1.OOE+02 5.24E+ 15 1.14E+03 1.62E+01 2.75E-01 7.30E+01 2.13E+00 2.69E-01 3.OOE+02 1.57E+16 2.29E+03 5.86E+01 4.42E-01 1.11E+02 8.04E+00 4.27E-01 1.OOE+03 5.24E+16 4.16E+03 1.89E+02 5.33E-01 1.18E+02 2.80E+01 4.92E-01 3.00E+03 1.57E+17 8.OOE+03 6.13E+02 7.27E-01 1.23E+02 1.10E+02 5.85E-01 1.OOE+04 5.24E+17 1.48E+04 1.62E+03 1.15E+00 1.33E+02 3.33E+02 7.59E-01 3.OOE+04 1.57E+18 2.69E+04 4.08E+03 2.19E+00 1.59E+02 8.72E+02 1.24E+00 1.OOE+05 5.24E+18 3.65E+04 8.02E+03 5.05E+00 2.43E+02 1.71E+03 3.31 E+00 3.OOE+05 1.57E+19 3.96E+04 1.47E+04 2.15E+01 7.89E+01 3.21 E+03 1.84E+01 1.OOE+06 5.24E+19 4.27E+04 2.07E+04 6.79E+01 2.37E+03 4.69E+03 6.35E+01 3.OOE+06 1.57E+20 4.75E+04 2.61 E+03 9.67E+01 3.35E+03 6.04E+03 9.10E+01 1.OOE+07 5.24E+20 5.46E+04 3.79E+04 1.01E+02 3.46E+03 8.98E+03 9.22E+01 3.OOE+07 1.57E+21 47

DOSE RESULTS Calculated doses for the assumed conditions and a mass of 1g at a neutron fluence rate of 1 E 13 cm-2s'I are given below for commonly used fissionable materials and those that were determined to be limiting. The total number of fissions varies based on the fission reaction cross-section.

Fast Fission of Th-232 Dry Rem Dry Rem Dry Rem Wet Rem Wet Rem Wet Rem Irradiation Total Bay WB Bay Thy Pub WB Bay WB Bay Thy Pub WB Seconds Fissions 1.82E-07 5.80E-10 1.04E-10 3.17E-08 7.80E-11 1.OOE-10 1.OOE+01 9.86E+05 5.04E-07 1.80E-09 2.62E-10 8.OOE-08 2.40E-10 2.51E-10 3.OOE+01 2.96E+06 1.29E-06 6.20E-09 5.92E-10 1.80E-07 8.50E-10 5.59E-10 1.OOE+02 9.86E+06 2.37E-06 1.85E-08 1.03E-09 3.01E-07 2.25E-09 9.69E-10 3.OOE+02 2.96E+07 3.82E-06 7.42E-08 1.51E-09 3.96E-07 1.20E-08 1.43E-09 1.OOE+03 9.86E+07 5.64E-06 2.38E-07 1.97E-09 4.17E-07 3.80E-08 1.86E-09 3.OOE+03 2.96E+08 8.11E-06 7.47E-07 2.96E-09 4.42E-07 1.36E-07 2.74E-09 1.OOE+04 9.86E+08 1.06E-05 1.88E-06 4.19E-09 4.72E-07 3.90E-07 3.73E-09 3.OOE+04 2.96E+09 1.40E-05 4.36E-06 5.38E-09 5.02E-07 9.25E-07 4.44E-09 1.OOE+05 9.86E+09 1.65E-05 7.59E-06 7.28E-09 5.58E-07 1.56E-06 5.77E-09 3.OOE+05 2.96E+10 1.88E-05 1.18E-05 1.68E-08 8.74E-07 2.41E-06 1.45E-08 1.OOE+06 9.86E+10 2.36E-05 1.50E-05 4.31E-08 1.77E-06 3.16E-06 4.01E-08 3.OOE+06 2.96E+11 3.39E-05 1.67E-05 5.92E-08 2.31E-06 3.59E-06 5.55E-08 1.OOE+07 9.86E+11 5.02E-05 2.01 E-05 6.07E-08 2.35E-06 4.43E-06 5.59E-08 3.OOE+07 2.96E+12 48

RESULTS FOR LIMITING f/s FOR MASS of lg and DRY IRRADIATION of U and Pu Irradiation Thermal Thermal Fast Thermal Fast Fast Fast Fast Seconds U-232 U-233 U-233 U-235 U-235 U-236 U-237 U-238 1.OOE+01 5.46E+ 11 4.27E+11 4.27E+1 1 3.29E+1 1 3.24E+ 11 2.97E+1 1 2.77E+ 11 2.67E+ 11 3.00E+01 1.99E+ 11 1.55E+ 11 1.55E+11 1.2 1E+11 1.20E+ 11 1.09E+ 11 1.03E+ 11 1.01E+11 1.OOE+02 7.46E+10 5.93E+10 5.92E+10 4.74E+10 4.76E+10 4.35E+10 4.14E+10 4.13E+10 3.OOE+02 3.65E+10 3.04E+10 2.96E+10 2.48E+10 2.47E+10 2.27E+10 2.19E+10 2.20E+ 10 1.OOE+03 2.03E+10 1.75E+10 1.64E+10 1.44E+10 1.41 E+ 10 1.30E+10 1.28E+10 1.29E+10 3.00E+03 1.31 E+10 1.14E+10 1.00E+10 9.40E+09 9.12E+09 8.49E+09 8.59E+09 8.88E+09 1.00E+04 9.34E+09 8.17E+09 6.57E+09 6.88E+09 6.48E+09 6.05E+09 6.25E+09 6.68E+09 3.OOE+04 8.06E+09 7.17E+09 5.OOE+09 6.09E+09 5.42E+09 4.98E+09 5.13E+09 5.59E+09 1.00E+05 6.84E+09 6.14E+09 3.71 E+09 5.35E+09 4.40E+09 3.97E+09 4.07E+09 4.56E+09 3.OOE+05 5.81 E+09 5.25E+09 3.08E+09 4.71 E+09 3.78E+09 3.38E+09 3.45E+09 3.95E+09 1.00E+06 4.29E+09 4.00E+09 2.58E+09 3.80E+09 3.15E+09 2.89E+09 2.96E+09 3.38E+09 3.OOE+06 2.63E+09 2.55E+09 1.90E+09 2.64E+09 2.31 E+09 2.21 E+09 2.28E+09 2.58E+09 1.OOE+07 1.73E+09 1.66E+09 1.38E+09 1.73E+09 1.59E+09 1.56E+09 1.63E+09 1.86E+09 3.00E+07 1.24E+09 1.15E+09 1.03E+09 1.16E+09 1.11E+09 1.11E+09 1.16E+09 1.31 E+09 Irradiation Fast Thermal Fast Thermal Fast Fast Fast Minimum fUs Seconds Pu-238 Pu-239 Pu-239 Pu-240 Pu-240 Pu-241 Pu-242 for U and Pu 1.OOE+01 3.78E+1 1 3.77E+1 1 3.74E+ 11 3.33E+ 11 3.36E+ 11 3.04E+ 11 2.91 E+ 11 2.67E+ 11 3.OOE+01 1.39E+ 11 1.39E+1 1 1.38E+ 11 1.22E+ 11 1.23E+11 1.12E+11 1.07E+11 1.01E+11 1.OOE+02 5.41 E+10 5.47E+ 10 5.38E+10 4.81E+10 4.84E+10 4.40E+10 4.17E+10 4.13E+10 3.00E+02 2.69E+10 2.73E+10 2.67E+10 4.23E+10 2.40E+10 2.18E+10 2.05E+10 2.05E+ 10 1.OOE+03 1.44E+10 1.48E+10 1.41 E+10 1.29E+10 1.27E+10 1.14E+10 1.03E+10 1.03E+10 3.OOE+03 8.82E+09 9.10E+09 8.51 E+09 7.87E+09 7.59E+09 6.76E+09 5.78E+09 5.78E+09 1.OOE+04 5.63E+09 5.91 E+09 5.23E+09 4.96E+09 4.59E+09 3.93E+09 3.02E+09 3.02E+09 3.OOE+04 3.92E+09 4.19E+09 3.42E+09 3.35E+09 2.97E+09 2.40E+09 1.64E+09 1.64E+09 1.OOE+05 2.61 E+09 2.87E+09 2.21 E+09 2.18E+09 1.91 E+09 1.48E+09 9.25E+08 9.25E+08 3.OOE+05 2.05E+09 2.28E+09 1.74E+09 1.71E+09 1.50E+09 1.15E+09 6.93E+08 6.93E+08 1.00E+06 1.80E+09 1.98E+09 1.55E+09 1.54E+09 1.35E+09 1.06E+09 6.45E+08 6.45E+08 3.OOE+06 1.46E+09 1.58E+09 1.30E+09 1.31E+09 1.18E+09 9.51 E+08 6.07E+08 6.07E+08 1.OOE+07 1.17E+09 1.23E+09 1.06E+09 1.07E+09 9.78E+08 8.18E+08 5.53E+08 5.53E+08 3.OOE+07 9.15E+08 9.58E+08 8.54E+08 8.48E+08 7.91 E+08 6.76E+08 4.86E+08 4.86E+08 49

RESULTS FOR LIMITING f/s FOR MASS of L, and WET IRRADIATION of U and Pu Irradiation Thermal Thermal Fast Thermal Fast Fast Fast Fast Seconds U-232 U-233 U-233 U-235 U-235 U-236 U-237 U-238 1.OOE+01 3.27E+12 2.74E+12 2.91E+12 2.58E+12 2.85E+12 2.80E+12 2.77E+12 2.74E+12 3.OOE+01 1.17E+12 1.03E+12 1.06E+12 9.73E+ 11 1.05E+12 1.06E+12 1.06E+12 1.09E+12 1.OOE+02 4.34E+1 1 4.02E+ 11 4.07E+1 1 3.79E+ 11 4.17E+11 4.21E+11 4.24E+ 11 4.55E+-11 3.OOE+02 2.16E+11 2.07E+ 11 2.09E+1 1 2.05E+1 1 2.21E+11 2.23E+1 1 2.22E+11 2.44E+1 1 1.OOE+03 1.46E+ 11 1.42 E+ 11 1.44E+ 11 1.44E+11 1.53E+11 1.55E+ 11 1.54E+ 11 1.70E+ 11 3.00E+03 1.37E+ 11 1.34E+ 11 1.35E+ 11 1.36E+ 11 1.45E+11 1.46E+ 11 1.46E+ 11 1.61 E+11 1.OOE+04 1.31 E+1 1 1.28E+ 11 1.29E+ 11 1.30E+ 11 1.38E+ 11 1.40E+ 11 1.40E+ 11 1.55E+11 3.00E+04 1.22E+ 11 1.19E+11 1.20E+ 11 1.22E+11 1.29E+ 11 1.32E+1 1 1.32E+11 1.46 E+11 1.OOE+05 1.08E+ 11 1.06E+11 1.07E+11 1.10 E+ 11 1.14E+11 1.18E+11 1.19E+11 1.29E+ 11 3.OOE+05 7.51E+10 7.75E+10 7.75E+10 8.56E+10 8.72E+10 9.23E+10 9.36E+10 9.97E+10 1.OOE+06 2.12E+10 2.43E+10 2.44E+10 3.53E+10 3.45E+10 3.97E+10 3.96E+10 4.16E+10 3.OOE+06 6.15E+09 7.09E+09 7.14E+09 1.08E+10 1.06E+10 1.22E+10 1.22E+10 1.28E+10 1.OOE+07 4.28E+09 4.93E+09 4.97E+09 7.61 E+09 7.43E+09 8.60E+09 8.56E+09 9.02E+09 3.OOE+07 4.22E+09 6.43E+09 4.91 E+09 7.53E+09 7.34E+09 8.51 E+09 8.48E+09 8.92E+09 Irradiation Fast Thermal Fast Thermal Fast Fast Fast Minimum f/s Seconds Pu-238 Pu-239 Pu-239 Pu-240 Pu-240 Pu-241 Pu-242 for U and Pu 1.OOE+01 4.50E+12 4.80E+12 4.92E+12 4.32E+12 4.35E+12 4.05E+12 3.86E+12 2.58E+12 3.OOE+01 1.65E+ 12 1.77E+12 1.80E+12 1.61 E+12 1.61 E+12 1.53E+12 1.50E+12 9.73E+1 1 1.00E+02 6.22E+ 11 6.71E+11 6.80E+ 11 6.18E+ 11 6.17E+11 5.93E+1 1 5.99E+ 11 3.79E+ 11 3.OOE+02 3.11E+11 3.27E+1 1 3.40E+ 11 3.10E+1 1 3.1OE+ 11 3.02E+ 11 3.08E+ 11 2.05E+ 11 1.OOE+03 2.08E+1 1 2.17E+11 2.27E+1 1 2.07E+ 11 2.08E+1 1 2.03E+ 11 2.09E+ 11 1.42E+11 3.OOE+03 1.96E+ 11 2.03E+1 1 2.13E+11 1.94E+11 1.95E+ 11 1.92E+ 11 1.98E+11 1.34E+11 1.OOE+04 1.87E+ 11 1.94E+11 2.03E+1 1 1.87E+ 11 1.87E+ 11 1.85E+ 11 1.90E+11 1.28E+ 11 3.OOE+04 1.74E+1 1 1.78E+ 11 1.87E+11 1.73E+ 11 1.74E+11 1.72E+ 11 1.77E+11 1.19E+11 1.00E+05 1.48E+1 1 1.48E+ 11 1.55E+ 11 1.48 E+ 11 1.47E+ 11 1.48E+ 11 1.53E+11 1.06E+ 11 3.OOE+05 9.69E+10 9.53E+10 9.98E+10 1.03E+ 11 1.02E+ 11 1.04E+ 11 1.11E+11 7.51 E+10 1.OOE+06 2.53E+10 6.86E+10 2.54E+10 3.14E+10 3.02E+10 3.35E+10 3.87E+10 2.12E+10 3.OOE+06 7.27E+09 4.75E+10 7.30E+09 9.23E+09 8.82E+09 9.88E+09 1.16E+10 6.15 E+09 1.00E+07 5.07E+09 3.83E+10 5.09E+09 6.48E+09 6.17E+09 6.93E+09 8.1OE+09 4.28E+09 3.OOE+07 5.01 E+09 2.72E+10 5.04E+09 6.40E+09 6.1OE+09 6.85E+09 8.OOE+09 4.22E+09 50

RESULTS FOR LIMITING f/s FOR MASS OF 1g and DRY IRRADIATON of OTHER FISSIONABLE MATERIALS Irradiation Thermal Thermal Fast Fast Fast Thermal Fast Thermal Thermal Thermal Seconds Th227 Th229 Th232 Pa231 Np237 Np237 Np238 Cf249 Cf251 Fm255 1.00E+01 4.31E+11 4.31E+11 2.71E+11 3.98E+11 3.47E+11 3.19E+11 3.06E+11 3.05E+11 2.69E+11 3.20E+11 3.00E+01 1.49E+11 1.49E+11 9.79E+10 1.45E+11 1.28E+11 1.18E+11 1.13E+11 1.05E+11 9.27E+10 1.13E+11 1.00E+02 5.45E+10 5.45E+10 3.82E+10 5.50E+10 5.08E+10 4.69E+10 4.51E+10 3.43E+10 3.16E+10 3.85E+10 3.00E+02 2.77E+10 2.77E+10 2.08E+10 2.78E+10 2.58E+10 2.44E+10 2.32E+10 1.18E+10 1.14E+10 1,37E+10 1.OOE+03 1.61E+10 1.61E+10 1.29E+10 1.55E+10 1.44E+10 1.40E+10 1.30E+10 3.50E+09 3.45E+09 4.05E+09 3.OOE+03 1.01E+10 1.01E+10 8.74E+09 9.55E+09 9.25E+09 9.17E+09 8.43E+09 1.23E+09 1.23E+09 1.43E+09 1.OOE+04 6.80E+09 6.79E+09 6.08E+09 6.17E+09 6.40E+09 6.53E+09 5.81E+09 4.24E+08 4.27E+08 4.94E+08 3.00E+04 5.66E+09 5.66E+09 4.65E+09 4.64E+09 4.99E+09 5.33E+09 4.36E+09 1.84E+08 1.85E+08 2,18E+08 1.OOE+05 4.65E+09 4.65E+09 3.52E+09 3.50E+09 3.73E+09 4.17E+09 3.15E+09 1.03E+08 1.00E+08 1.23E+08 3.OOE+05 4.03E+09 4.04E+09 2.99E+09 2.97E+09 3.08E+09 3.50E+09 2.58E+09 8.12E+07 7.75E+07 9.85E+07 1.OOE+06 3.29E+09 3.29E+09 2.62E+09 2.57E+09 2.62E+09 2.94E+09 2.25E+09 7.77E+07 7.43E+07 9.47E+07 3.00E+06 2.31E+09 2.30E+09 2.09E+09 1.97E+09 1.99E+09 2.21E+09 1.81E+09 7.72E+07 7.38E+07 9.38E+07 1.00E+07 1.54E+09 1.54E+09 1.45E+09 1.42E+09 1.47E+09 1.56E+09 1.38E+09 7.60E+07 7.29E+07 9.28E+07 3.OOE+07 1.04E+09 1.04E+09 9.82E+08 1.042+09 1.08E+09 1.10E+09 1.04E+09 7.46E+07 7.16E+07 9.13E+07 Irradiation Fast Fast Fast Thermal Fast Fast Thermal Fast Thermal Fast Seconds 242Cm Cm243 Cm244 Cm245 Cm246 Cm248 Am241 Am241 Am242 Am243 1.00E+01 4.65E+11 3.96E+11 3.49E+11 2.93E+11 2.89E+11 2.67E+11 3.45E+11 3.97E+11 3.44E+11 3.39E+11 3.OOE+01 1.69E+11 1.44E+11 1.26E+11 1.04E+11 1.04E+11 9.43E+10 1.26E+11 1.462+11 1.26E+11 1.24E+11 1.00E+02 6.15E+10 5.20E+10 4.61E+10 3.72E+10 3.79E+10 3.46E+10 4.80E+10 5.48E+10 4.80E+10 4.70E+10 3.00E+02 2.65E+10 2.24E+10 2.00E+10 1.51E+10 1.63E+10 1.44E+10 2.31E+10 2.56E+10 2.30E+10 2.18E+10 1.00E+03 1.13E+10 9.26E+09 8.06E+09 5.37E+09 6.28E+09 5.18E+09 1.14E+10 1.22E+10 1.14E+10 1.01E+10 3.00E+03 5.16E+09 4.11E+09 3.54E+09 2.13E+09 2.63E+09 2.06E+09 6.30E+09 6.37E+09 6.29E+09 5.02E+09 1.00E+04 2.15E+09 1.69E+09 1.44E+09 7.85E+08 1.03E+09 7.63E+08 3.28E+09 3.12E+09 3.27E+09 2.29E+09 3.00E+04 1.03E+09 8.09E+08 6.76E+08 3.49E+08 4.70E+08 3.39E+08 1.76E+09 1.61E+09 1.77E+09 1.14E+09 1.00E+05 5.92E+08 4.71E+08 3.82E+08 1.89E+08 2.58E+08 1.83E+08 9.72E+08 8.68E+08 9.73E+08 6.27E+08 3.00E+05 4.71E+08 3.78E+08 3.00E+08 1.45E+08 1.98E+08 1.40E+08 7.17E+08 6.36E+08 7.17E+08 4.71E+08 1.00E+06 4.45E+08 3.59E+08 2.86E+08 1.38E+08 1.88E+08 1.34E+08 6.62E+08 5.86E+08 6.61E+08 4.43E+08 3.00E+06 4.22E+08 3.46E+08 2.77E+08 1.36E+08 1.85E+08 1.32E+08 6.14E+08 5.48E+08 6.13E+08 4.22E+08 1.00E+07 3.94E+08 3.27E+08 2.66E+08 1.33E+08 1.80E+08 1.30E+08 5.51E+08 5.02E+08 5.51E+08 3.94E+08 3.00E+07 3.64E+08 3.05E+08 2.49E+08 1.29E+08 1.72E+08 1.25E+08 4.79E+08 4.52E+08 4.79E+08 3.59E+08 51

RESULTS FOR LIMITING f/s FOR MASS OF ig and WET IRRADIATION of OTHER FISSIONABLE MATERIALS Irradiation Thermal Thermal Fast Fast Fast Thermal Fast Thermal Thermal Thermal Seconds Th227 Th229 Th232 Pa231 Np237 Np237 Np238 Cf249 Cf251 Fm255 1.00E+01 1.94E+12 2.07E+12 1.56E+12 2.69E+12 4.00E+12 3.62E+12 3.83E+12 8.42E+12 6.52E+12 6.55E+12 3.00E+01 7.30E+11 7.58E+11 6.16E+11 9.63E+11 1.47E+12 1.34E+12 1.41E+12 3.07E+12 2.40E+12 2.35E+12 1.00E+02 2.88E+11 2.93E+11 2,74E+11 3.58E+11 5.63E+11 5.12E+11 5.32E+11 1.13E+12 8.83E+11 8.41E+11 3.00+E02 1.52E+11 1.54E+11 1.64E+11 1.81E+11 2.85E+11 2.62E+11 2.67E+11 5.45E+11 4.27E+11 3.98E+11 1.00E+03 1.07E+11 1.08E+11 1.25E+11 1.24E+11 1.94E+11 1.78E+11 1.80E+11 3.57E+11 2.79E+11 2.58E+11 3.00E+03 1.01E+11 1.02E+11 1.18E+11 1.16E+11 1.81E+11 1.67E+11 1.69E+11 3.33E+11 2.61E+11 2.41E+11 1.00E+04 9.64E+10 9.68E+10 1.12E+11 1.10E+11 1.73E+11 1.60E+11 1.62E+11 3.17E+11 2.55E+11 2.34E+11 3.00E+04 9.08E+10 9.12E+10 1.04E+11 1.03E+11 1.60E+11 1.49E+11 1.52E+11 2.84E+11 2.42E+11 2.17E+11 1.00E+05 8.37E+10 8.40E+10 9.82E+10 9.39E+10 1.37E+11 1.30E+11 1.33E+11 2.16E+11 2.13E+11 1.82E+11 3.OOE+05 6.87E+10 6.90E+10 8.84E+10 7.58E+10 9.54E+10 9.48E+10 9.63E+10 1.12E+11 1.58E+11 1.20E+11 1.OOE+06 3.10E+10 3.10E+10 5.64E+10 3.29E+10 2.82E+10 3.26E+10 3.18E+10 2.10E+10 6.11E+10 3.29E+10 3.00E+06 9.40E+09 9.40E+09 2.46E+10 1.02E+10 8.29E+09 9.79E+09 9.52E+09 6.09E+09 2.21E+10 9.61E+09 1.00E+07 6.58E+09 6.57E+09 1.78E+10 7.16E+09 5.79E+09 6.87E+09 6.68E+09 4.25E+09 1.58E+10 6.67E+09 3.00E+07 6.48E+09 6.47E+09 1.76E+10 7.07E+09 5.71E+09 6.80E+09 6.61E+09 4.19E+09 1.53E+10 6.56E+09 Irradiation Fast Fast Fast Thermal Fast Fast Thermal Fast Thermal Fast Seconds 242Cm Cm243 Cm244 Cm245 Cm246 Cm248 Am241 Am241 Am242 Am243 1.00E+01 8.98E+12 6.80E+12 5.80E+12 4.82E+12 4.78E+12 4.03E+12 5.67E+12 6.01E+12 5.67E+12 5.41E+12 3.00E+01 3.14E+12 2.43E+12 2.10E+12 1.81E+12 1.77E+12 1.58E+12 2.04E+12 2.19E+12 1.98E+12 1.94E+12 1.00E+02 1.11E+12 8.75E+11 7.72E+11 7.12E+11 6.74E+11 6.33E+11 7.44E+11 8.13E+11 7.37E+11 6.97E+11 3.00E+02 5.13E+11 4.17E+11 3.74E+11 3.69E+11 3.36E+11 3.27E+11 3.61E+11 3.97E+11 3.59E+11 3.34E+11 1.00E+03 3.29E+11 2.71E+11 2.46E+11 2.49E+11 2.23E+11 2.20E+11 2.38E+11 2.62E+11 2.36E+11 2.18E+11 3.00E+03 3.06E+11 2.53E+11 2.31E+11 2.35E+11 2.11E+11 2.07E+11 2.21E+11 2.46E+11 2.22E+11 2.04E+11 1.00E+04 2.91E+11 2.43E+11 2.23E+11 2.24E+11 2.05E+11 2.03E+11 2.13E+11 2.34E+11 2.13E+11 1.97E+11 3.00E+04 2.63E+11 2.25E+11 2.10E+11 2.10E+11 1.95E+11 1.95E+11 1.97E+11 2.14E+11 1.97E+11 1.84E+11 1.00E+05 2.06E+11 1.89E+11 1.82E+11 1.79E+11 1.75E+11 1.79E+11 1.65E+11 1.75E+11 1.65E+11 1.58E+11 3.002+05 1.15E+11 1.20E+11 1.27E+11 1.23E+11 1.36E+11 1.48E+11 8.78E+10 1.05E+11 1.082+11 1.09E+11 1.00E+06 2.32E+10 2.92E+10 3.75E+10 3.55E+10 5.49E+10 7.26E+10 2.83E+10 2.29E+10 2.85E+10 3.19E+10 3.00E+06 6.64E+09 8.34E+09 1.09E+10 1.02E+10 1.64E+10 2.37E+10 8.25E+09 6.51E+09 8.25E+09 9.28E+09 1.00E+07 4.62E+09 5.79E+09 7.56E+09 7.06E+09 1.15E+10 1.67E+10 5.77E+09 4.52E+09 5.75E+09 6.50E+09 3.00E+07 4.56E+09 5.71E+09 7.45E+09 6.97E+09 1.13E+10 1.63E+10 5.69E+09 4.47E+09 5.68E+09 6.42E+09 52

RESULTS FOR LIMITING f/s FOR MASS OF l2 and WET IRRADIATION The f/s calculations for all of the fissionable materials and irradiation conditions above were compared and the minimum f/s value for each irradiation time was determined. Dry sample conditions are limiting and apply to wet sample conditions at the time of unloading. Wet f/s values listed are for all fissionable materials (U, Pu, and All Others).

Irradiation Dry f/s Dry fUs Wet fls Seconds U, Pu Others All 1.00E+01 2.67E+ 11 2.67EE+ 11 1.56E+12 3.00E+01 1.01 E+11 9.27E+10 6.16E+ 11 1.00E+02 4.13E+10 3.16E+10 2.74E+ 11 3.00E+02 2.05E+10 1.14E+10 1.52E+ 11 1.00E+03 1.03E+10 3.45E+09 1.07E+1 1 3.00E+03 5.78E+09 1.23E+09 1.01 E+11 1.OOE+04 3.02E+09 4.24E+08 9.64E+10 3.00E+04 1.64E+09 1.84E+08 9.08E+10 1.00E+05 9.25E+08 1.00E+08 8.37E+10 3.00E+05 6.93E+08 7.75E+07 6.87E+10 1.00E+06 6.45E+08 7.43E+07 2.10E+10 3.00E+06 6.07E+08 7.38E+07 6.09E+09 1.00E+07 5.53E+08 7.29E+07 4.25E+09 3.00E+07 4.86E+08 7.16E+07 4.19E+09 Estimated trend line results for limiting fission rates are as follows:

Estimated to Irradiation Estimated Estimated Calculated Ratio time (s) f/s U and Pu f/s Others U and Pu Others 1.OOE+01 2.67E+11 2.66E+11 9.97E-01 9.98E-01 3.OOE+01 9.94E+10 9.07E+10 9.87E-01 9.78E-01 1.OOE+02 4.10E+10 2.79E+10 9.92E-01 8.84E-01 3.OOE+02 1.97E+10 9.56E+09 9.62E-01 8.39E-01 1.OOE+03 9.18E+09 2.99E+09 8.88E-01 8.65E-01 3.OOE+03 4.73E+09 1.06E+09 8.19E-01 8.65E-01 1.OOE+04 2.43E+09 3.74E+08 8.03E-01 8.83E-01 3.OOE+04 1.43E+09 1.72E+08 8.72E-01 9.33E-01 1.OOE+05 9.14E+08 9.93E+07 9.88E-01 9.88E-01 3.OOE+05 6.88E+08 7.74E+07 9.93E-01 1.OOE+00 1.OOE+06 5.67E+08 6.91 E+07 8.80E-01 9.30E-01 3.OOE+06 5.13E+08 6.62E+07 8.45E-01 8.96E-01 1.OOE+07 4.81E+08 6.46E+07 8.71 E-01 8.86E-01 3.OOE+07 4.65E+08 6.37E+07 9.57E-01 8.89E-01 53

Comparison of Atom and Activity Calculations to Nuclear Analysis 1.0 Activities of those nuclides that gave the higher doses were compared for thermal fission of U-235. A total of 50 nuclides were evaluated at a short irradiation time of 1000 seconds and a long irradiation time of 1E6 seconds.

Comparison of the data indicates the calculated values for most nuclides exceed those given determined from Nuclear Analysis 1.0. The main reason for this difference is the reference used for branching fraction and half-life data. The same reference was used for individual fission yields.

" Branching fraction used in Nuclear Analysis 1.0 was taken from the "Table of Radioactive Isotopes:

Eight Edition", E. Browne, RB Firestone, VS Shirley, eds. John Wiley & Sons, pub, 1986.

" Decay constant data used in Nuclear Analysis 1.0 was taken from the "Table of Radioactive Isotopes: Eight Edition", E. Browne, RB Firestone, VS Shirley, eds. John Wiley & Sons, pub, 1986 and from Evaluation and Compilation of Fission Product Yields, T.R. England and B.F. Rider, Los Alamos National Laboratory, October, 1994, LA-UR 94-3106 ENDF 349.

" Branching fraction and decay constant data for the calculated values was taken from "Nuclear Energy Agency (NEA) Publication 6287 "Joint Evaluated Fission and Fusion Project Report 20" (JEFF 3.1-3.1.1 Radioactive Decay Data and Fission Yield Sub-Library), MA Kellett, 0. Bersillon, RW Mills, eds., OECD pub, 2009.

" Fission yield data was taken from Evaluation and Compilation of Fission Product Yields, T.R.

England and B.F. Rider, Los Alamos National Laboratory, October, 1994, LA-UR 94-3106 ENDF 349, for the calculated and Nuclear Analysis 1.0.

As an example of affect that the decay branching fraction has consider the mass chain of A = 133.

JEFF Report 20 and Nuclear Analysis 1.0 has the following decay branching fractions:

JEFF Report 20 Nuclear Analysis 1.0 Nuclide B- B-,m IT B- B-,m IT Sn-133 1 1 Sb-133 0.8271 0.1729 1 Te-133m 0.825 0.175 0.83 0.17 Te-133 1 1 1-133 0.9715 0.0285 1 Xe-133m 1 1 Xe-133 1 1 54

From the JEFF Report 20 decay branching fractions, there are 6 decay pathways:

1. Sn-133 to Sb-133 to Te-133m to Te-133 to 1-133 to Xe-133m to Xe-133

2. Sn-133 to Sb-133 to Te-133m to Te-133 to 1-133 to Xe-133

3. Sn-133 to Sb-133 to Te-133m to 1-133 to Xe-133m to Xe-133

4. Sn-133 to Sb-133 to Te-133m to 1-133 to Xe-133

5. Sn-133 to Sb-133 to Te-133 to 1-133 to Xe-133m to Xe-133

6. Sn-133 to Sb-133 to Te-133 to 1-133 to Xe-133 From the Nuclear Analysis 1.0 decay branching fractions, there are 4 decay pathways:

1. Sn-133toSb-133toTe-133mtoTe-133to1-133toXe-133mtoXe-133

2. Te-133mto Te-133 to 1-133 to Xe-133

3. Te-133mto 1-133 toXe-133

4. Xe-133mtoXe-133 A comparison of the results between the equations used in this calculation for the 4 and 6 pathway and the 4 pathway Nuclear Analysis 1.0 decay branching fractions for two cases:

Case 1: t = 1.73E5 s, T = 0 s Calculated Atoms Nuclear Analysis 1.0 Atoms Nuclide 6 pathway 4 pathway 4 pathway Sn-133 4.3E10 4.3E10 4.29E10 Sb-133 7.78E13 7.78E13 7.75E13 Te-133m 2.45E15 2.15E15 2.14E15 Te-133 6.0E14 6.53E14 6.63E14 1-133 1.01E17 1.01E17 8.79E16 Xe-133m 2.41E15 3.63E13 3.61E13 Xe-133 9.23E16 9.46E16 7.98E16 Case 2: t = 1.000 E3 s, T = 1.000 E3 s Calculated Atoms Nuclear Analysis 1.0 Atoms Nuclide 6 pathway I pathway 4 pathway Sn-133 0 0 0 Sb-133 7.59E1 1 7.59E1 1 7.57E11 Te-133m 3.76E14 3.28E14 3.28E14 Te-133 1.2E14 1.32E14 1.68E14 1-133 4.29E14 1.6E14 5.05E14 Xe-133m 4.06E1 1 2.82El 1 2.81E1 1 Xe-133 1.24E12 1.3E12 4.3E12 All of the above are in good agreement with the exception of Xe-133m and Xe-133. Nuclear Analysis 1.0 does not list a IT decay branching fraction for Xe- 133m, which affects the atom calculations for both Xe-133m and Xe-133.

55

Two cases were compared for activities and radiation dose for 50 nuclides produced by the thermal fission of U-235 as described below. Data for the two cases is provided on the following pages.

Calculated activities have median and average values of approximately 1.3 times and 1.7 times of those determined by Nuclear Analysis 1.0 at t = 1E3 seconds (based on occupational whole body dose)

Ratio of Calculated to Nuclear Analysis 1.0 for: T=0s T=IE3s Median 1.467 1.219 Minimum 0.584 0.294 Maximum 6.753 10.03 Average 1.707 1.612 Calculated activities have median and average values of approximately 1.6 times and 1.7 times of those determined by Nuclear Analysis 1.0 at t = 1E6 seconds (based on occupational whole body dose)

Ratio of Calculated to Nuclear Analysis 1.0 for: T=0s Median 1.59E+00 Minimum 4.07E-01 Maximum 4.61 E+00 Average 1.69E+00 Dose comparisons by thermal fission of 1 g of U-235 at a neutron fluence rate of 1 El3 cm2sl:

Time, s Calculated Nuclear Analysis Limiting Calculated vs rem rem Dose Category Nuclear Analysis t=lE3, T=0 2.06E2 1.48E2 Effective 1.39 t=lE3, T=IE3 3.86E1 2.60E1 Dose-Equivalent 1.48 t=l E6, T=0 5.68E2 4.4 1E2 Effective 1.29 Dose-Equivalent Summary of Comparison The JEFF Report 20 decay branching fractions are more recent and differ from those used in Nuclear Analysis 1.0. As a result, decay chain pathways are different which in turn causes a difference in the calculated atom populations and activities.

For the limiting cases compared above, nuclide activities in this calculation are within a factor of 2 higher on average than those determined by Nuclear Analysis 1.0 whether based on activity or dose considerations.

56

Neutron energy - Thermal Target = U235 Mass = 1.00E+00 9 Fluence rate - 1.OOE+13 cm-2s-1 Irradiation time, t - 1.00E+03 s Decay time, T = 1.00E+03 S Calcuated Nuclear Analysis 1.0 Calculated vs Nuclear A(t) A(t+T) A(t) A(t+T) Analysis 1.0 uCi uCi uCi uCi A(t) A(t+T)

Nuclide 1.27E+03 3.79E+02 9.53E+02 3.02E+02 1.34E+00 1.25E+00 Ga74 2.53E+05 7.20E+04 1.29E+05 3.73E+04 1.96E+00 1.93E+00 As79 3.05E+06 8.82E+04 3.33E+06 1.01 E+05 9.16E-01 8.73E-01 Se84 6.18E+05 8.98E+05 2.82E+05 5.62E+05 2.19E+00 1.60E+00 Rb88 3.64E+07 4.65E+05 2.03E+07 3.05E+05 1.79E+00 1.52E+00 Rb90 8.32E+05 8.77E+05 4.38E+05 4.67E+05 1.90E+00 1.88E+00 Sr9l 3.11 E+07 6.59E+06 1.96E+07 4.13E+06 1.59E+00 1.60E+00 Sr93 Y93 3.69E+05 4.37E+05 2.39E+05 4.19E+05 1.55E+00 1.04E+00 5.85E+03 1.11E+04 1.32E+03 2.67E+03 4.44E+00 4.15E+00 Zr95 7.35E+05 7.27E+05 2.76E+05 2.73E+05 2.66E+00 2.66E+00 Zr97 Mo99 8.47E+04 8.56E+04 7.03E+04 7.23E+04 1.20E+00 1.18E+00 Mo101 3.27E+07 1.50E+07 1.15E+07 5.21 E+06 2,84E+00 2.88E+00 1.16E+07 1.72E+07 4.01E+06 5.96E+06 2.90E+00 2.89E+00 Tcl01 Mo102 2.04E+07 7.40E+06 1.11E+07 3.99E+06 1.83E+00 1.86E+00 2.20E+07 7.46E+06 1.11E+07 4.OOE+06 1.98E+00 1.87E+00 Tc0 02 Rul05 1.29E+05 2.35E+05 6.74E+04 1.27E+05 1.92E+00 1.85E+00 1.03E+03 1.40E+03 1.76E+03 1.97E+03 5.84E-01 7.13E-01 Ag113 Sn125m 9.31 E+04 2.77E+04 2.98E+04 8.83E+03 3.12E+00 3.13E+00 Sn129 1.34E+06 7.54E+03 1.14E+06 9.24E+03 1.18E+00 8.16E-01 Sb130m 8.10E+06 2.04E+06 1.20E+06 2.03E+05 6.75E+00 1.OOE+01 Sn130 4.47E+06 2.OOE+05 4.57E+06 2.01 E+05 9.77E-01 9.96E-01 1.85E+07 1.01E+07 1.08E+07 5.96E+06 1.71E+00 1.70E+00 Bal41 5.68E+05 1.22E+06 2.90E+05 6.75E+05 1.96E+00 1.80E+00 Lal4l 1.54E+07 3.83E+05 1.56E+07 3.77E+05 9.86E-01 1.02E+00 Ce145 Pr149 4.33E+06 2.93E+04 4.33E+06 2.88E+04 9.99E-01 1.02E+00 Nd152 6.82E+05 2.48E+05 6.81 E+05 2.47E+05 1.OOE+00 1.01E+00 5.04E+05 3.54E+05 5.07E+05 3.51 E+05 9.95E-01 1.01 E+00 Pm152 5.52E+05 7.22E+04 5.53E+05 7.13E+04 9.99E-01 1.01 E+00 Pm153 4.OOE+06 2.52E+06 4.00E+06 2.48E+06 1.OOE+00 1.01E+00 Sbl31 Tel31m 7.85E+03 9.47E+03 5.60E+03 5.57E+03 1.40E+00 1.70E+00 9.15E+05 5.77E+05 9.99E+05 1.80E+06 9.16E-01 3.21E-01 Tel31 1131 7.94E+02 1.53E+03 4.05E+02 1.90E+03 1.96E+00 8.04E-01 2.80E+04 3.43E+04 3.80E+04 5.03E+04 7.38E-01 6.82E-01 Te132 1132 7.82E+03 9.81E+03 7.36E+03 1.05E+04 1.06E+00 9.34E-01 2.53E+06 2.12E+06 2.28E+06 1.85E+06 1.11E+00 1.15E+00 Tel 33m 7.07E+06 3.03E+06 7.91 E+06 4.24E+06 8.94E-01 7.15E-01 Tel 33 1133 6.43E+04 1.07E+05 5.27E+04 1.26E+05 1.22E+00 8.52E-01 Tel 34 7.26E+06 5.51 E+06 6.77E+06 5.14E+06 1.07E+00 1.07E+00 2.75E+06 3.45E+06 1.33E+06 2.31 E+06 2.07E+00 1.49E+00 1134 1135 1.42E+06 1.40E+06 7.27E+05 7.15E+05 1.95E+00 1.96E+00 Br84m 5.78E+04 8.43E+03 5.79E+04 8.44E+03 9.98E-01 9.99E-01 2.49E+06 1.97E+06 8.07E+05 8.14E+05 3.09E+00 2.41 E+00 Br84 Br85 4.88E+06 9.64E+04 3.19E+06 6.53E+04 1.53E+00 1.48E+00 2.08E+06 1.87E+06 1.35E+06 1.24E+06 1.54E+00 1.51E+00 Kr87 Kr88 1.24E+06 1.17E+06 8.91 E+05 8.40E+05 1.39E+00 1.39E+00 1.78E+07 4.57E+05 1.78E+07 4.60E+05 1.OOE+00 9.93E-01 Kr89 4.71 E+01 4.71 E+01 3.29E+01 1.75E+02 1.43E+00 2.69E-01 Xe133 Xe135 4.85E+04 6.11E+04 1.86E+04 3.90E+04 2.61 E+00 1.57E+00 2.30E+07 1.19E+06 2.39E+07 1.22E+06 9.64E-01 9.73E-01 Xe137 1.42E+07 6.29E+06 1.43E+07 6.30E+06 9.95E-01 9.99E-01 Xe138 57

Neutron energy = Thermal Target = U235 Mass = 1.OOE+00 g Fluence rate = 1.OOE+13 cm-2s-1 Irradiation time = 1.OOE+06 s Decay time = O.OOE+00 s Calcuated Nuclear Analysis 1.0 Calculated vs Nuclear Nuclide A(t) uCi A(t) uCi Analysis A(t)

Ga74 1.83E+03 1.34E+03 1.36E+00 As79 3.57E+05 1.80E+05 1.98E+00 Se84 3.14E+06 3.41E+06 9.21E-01 Rb88 3.33E+07 1.37E+07 2.43E+00 Rb9O 3.70E+07 2.05E+07 1.80E+00 Sr91 4.55E+07 2.36E+07 1.93E+00 Sr93 3.95E+07 2.46E+07 1.61E+00 Y93 3.96E+07 2.51E+07 1.58E+00 Zr95 1.43E+07 3.11E+06 4.61E+00 Zr97 6.45E+07 2.41E+07 2.68E+00 Mo99 2.83E+07 2.19E+07 1.29E+00 Mo101 6.03E+07 2.08E+07 2.90E+00 Tcl1O 6.18E+07 2.08E+07 2.97E+00 Mo102 3.19E+07 1.72E+07 1.86E+00 Tcl02 3.46E+07 1.72E+07 2.01E+00 RulO5 6.72E+06 3.44E+06 1.95E+00 Ag113 3.75E+04 5.66E+04 6.62E-01 Kr90 2.14E+07 1.99E+07 1.07E+00 Sn129 1.35E+06 1.04E+06 1.30E+00 KrgI 1.36E+07 1.36E+07 9.98E-01 S0130 4.68E+06 4.75E+06 9.84E-01 Ba141 4.04E+07 2.35E+07 1.72E+00 La141 4.72E+07 2.35E+07 2.01E+00 Ce145 1.58E+07 1.59E+07 9.92E-01 Pr149 4.35E+06 4.33E+06 1.01E+00 Nd152 1.07E+06 1.06E+06 1.01E+00 Pm152 1.08E+06 1.07E+06 1.01E+00 Pm153 6.34E+05 6.29E+05 1.01E+00 Sb131 1.04E+07 1.02E+07 1.02E+00 Cs138 4.60E+07 2.63E+07 1.75E+00 Te131 1.06E+07 1.06E+07 1.OOE+0O 1131 1.27E+07 6.73E+06 1.89E+00 Te132 1.28E+07 1.27E+07 1.OOE+00 1132 2.17E+07 1.27E+07 1.71E+00 Cs137 1.79E+04 1.82E+04 9.86E-01 Te133 1.51E+07 1.42E+07 1.06E+00 1133 3.18E+07 1.49E+07 2.14E+00 Te134 3.02E+07 2.80E+07 1.08E+00 1134 8.41E+07 3.OOE+07 2.80E+00 1135 4.99E+07 2.53E+07 1.97E+00 Kr85 2.78E+03 6.84E+03 4.07E-01 Br84 1.09E+07 3.48E+06 3.13E+00 Br85 4.99E+06 3.23E+06 1.54E+00 Kr87 1.58E+07 8.26E+06 1.91E+00 Kr88 1.92E+07 1.01E+07 1.90E+00 Kr89 1.83E+07 1.82E+07 1.OOE+00 Xe133 2.44E+07 1.11E+07 2.20E+00 Xe135 5.25E+07 1.15E+07 4.57E+00 Xe137 2.43E+07 2.50E+07 9,72E-01 58 Xe138 2.55E+07 2.54E+07 1.00E+00

Comparison to TS Amendment 17 Fission Rate Limits:

TS 17 used cumulative fission yields and TS 18 used individual fission yields with a time dependent activity buildup from production and decay. Cumulative yields assume all precursors have decayed to the nuclide being evaluated. However in TS 18, activities calculated are based on the production and decay kinetics.

For U and Pu nuclides, the TS 18 to TS 17 f/s ratio ranges from -0.5 to 9 f/s with a median of- 4.2.

TS 18 f/s limits are less than or similar to those for TS 17 up to - 3600 s (1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />). TS 18 f/s limits exceed those in TS 17 after 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, with a maximum of- 9 times higher at 130 hours0.0015 days <br />0.0361 hours <br />2.149471e-4 weeks <br />4.9465e-5 months <br /> (4.68E5 s).

For other fissionable materials, the TS 18 to TS 17 f/s ratio ranges from -0.2 to 1, with a median at -

0.5. TS 18 f/s limits are consistently less than those given in TS 17 for other fissionable materials.

This is primarily caused by considering fissionable materials with higher cross-sections TS 18 f/s limits are less than those in TS 17 for irradiation times less than - 130 hours0.0015 days <br />0.0361 hours <br />2.149471e-4 weeks <br />4.9465e-5 months <br /> (4.68E5 s) and are similar for irradiation times after 130 hours0.0015 days <br />0.0361 hours <br />2.149471e-4 weeks <br />4.9465e-5 months <br />.

Comparison of f/s limits in TS 18 and TS 17 is illustrated below:

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Comparison to TS 17 Fission Rate Limits:

Others U,Pu Others U,Pu Others U,Pu Time~s TS 18 TS1 8 TS 17 TS18 vs TS17 Ratios TS1 8/TSI 7 TS18/TS17 6.00E+01 4.60E+10 5.88E+10 1.25E+11 3.68E-01 4.70E-01 1.20E+02 2.34E+10 3.62E+10 7.12E+10 3.28E-01 5.08E-01 Median = 4.58E-01 4.20E+00 1.80E+02 1.57E+10 2.75E+10 5.16E+10 3.05E-01 5.34E-01 Minimum = 2.06E-01 4.70E-01 3.00E+02 9.56E+09 1.97E+10 3.45E+10 2.77E-01 5.71E-01 Maximum = 1.08E+00 8.85E+00 6.OOE+02 4.88E+09 .1.26E+10 1.99E+10 2.45E-01 6.34E-01 Average = 5.87E-01 4.50E+00 1.20E+03 2.51 E+09 8.20E+09 1.13E+10 2.22E-01 7.25E-01 1.80E+03 1.71 E+09 6.41 E+09 8.04E+09 2.13E-01 7.98E-01 2.40E+03 1.31E+09 5.40E+09 6.27E+09 2.08E-01 8.62E-01 3.OOE+03 1.06E+09 4.73E+09 5.14E+09 2.07E-01 9.21E-01 3.60E+03 9.01 E+08 4.26E+09 4.38E+09 2.06E-01 9.73E-01 7.20E+03 4.90E+08 2.89E+09 2.35E+09 2.08E-01 1.23E+00 1.08E+04 3.52E+08 2.33E+09 1.62E+09 2.17E-01 1.44E+00 1.44E+04 2.82E+08 2.02E+09 1.22E+09 2.32E-01 1.66E+00 1.80E+04 2.40E+08 1.81E+09 9.82E+08 2.45E-01 1.84E+00 2.16E+04 2.12E+08 1.66E+09 8.23E+08 2.57E-01 2.02E+00 2.52E+04 1.92E+08 1.55E+09 7.11 E+08 2.70E-01 2.18E+00 2.88E+04 1.76E+08 1.46E+09 6.27E+08 2.82E-01 2.33E+00 3.24E+04 1.65E+08 1.39E+09 5.61 E+08 2.93E-01 2.48E+00 3.60E+04 1.55E+08 1.33E+09 5.08E+08 3.05E-01 2.61 E+00 7.20E+04 1.12E+08 1.02E+09 2.71 E+08 4.11E-01 3.76E+00 1.08E+05 9.69E+07 8.93E+08 1.92E+08 5.05E-01 4.65E+00 1.44E+05 8.94E+07 8.21 E+08 1.53E+08 5.85E-01 5.37E+00 1.80E+05 8.49E+07 7.74E+08 1.30E+08 6.53E-01 5.95E+00 2.16E+05 8.18E+07 7.40E+08 1.15E+08 7.12E-01 6.44E+00 2.52E+05 7.96E+07 7.14E+08 1.04E+08 7.64E-01 6.86E+00 2.88E+05 7.79E+07 6.94E+08 9.62E+07 8.10E-01 7.21E+00 3.24E+05 7.66E+07 6.77E+08 9.04E+07 8.47E-01 7.49E+00 3.60E+05 7.55E+07 6.63E+08 8.57E+07 8.81E-01 7.74E+00 3.96E+05 7.47E+07 6.52E+08 7.90E+07 9.45E-01 8.25E+00 4.32E+05 7.39E+07 6.42E+08 7.45E+07 9.92E-01 8.61E+00 4.68E+05 7.33E+07 6.33E+08 7.15E+07 1.03E+00 8.85E+00 7.20E+05 7.06E+07 5.92E+08 6.76E+07 1.04E+00 8.75E+00 1.08E+06 6.88E+07 5.62E+08 6.40E+07 1.08E+00 8.78E+00 1.44E+06 6.79E+07 5.45E+08 6.31 E+07 1.08E+00 8.64E+00 1.80E+06 6.73E+07 5.34E+08 6.28E+07 1.07E+00 8.50E+00 2.16E+06 6.68E+07 5.25E+08 6.28E+07 1.06E+00 8.37E+00 4.32E+06 6.56E+07 5.01E+08 6.28E+07 1.04E+00 7.98E+00 4.32E+06 6.56E+07 5.01 E+08 6.28E+07 1.04E+00 7.98E+00 1.73E+07 6.41 E+07 4.72E+08 6.28E+07 1.02E+00 7.52E+00 3.15E+07 6.36E+07 4.65E+08 6.28E+07 1.01E+00 7.40E+00 60

CONCLUSIONS

1. The limiting fission rate (f/s) based on dose limitations for irradiation time up to 1 year and decay times up to 1 year is approximated by the following equations:

Estimated line equation for Isotopes of U and Pu:

(f / s) = 4.7E1 2[t-"'7 ] + 7.7E1 1[t- 65] + 5.4E8[t-° 1]

Estimated line equation for All Other Fissionable Materials:

(f / s) = 2.54E12[t-° 98'] + 7.55E7[t-° 1]

Where, (f/s) is the limiting fission rate for irradiation time "t" "t" is in seconds and is limited to 3.15 E7 s (1 year)

For the purposes of Technical Specifications, the fission rate at 10 seconds applies to all irradiation times up to 10 seconds and the irradiation time is limited to 1 year.

The approximated fission rate (f/s) is based on the following dose limits:

• ,0.5 rem total effective dose-equivalent to occupational personnel

• 5 rem committed dose-equivalent to the thyroid

• 0.01 rem total effective dose-equivalent to members of the public Dry sample results were determined to be more limiting. Wet samples were analyzed to determine the limiting fission rates prior to sample unloading, i.e. failure while still wet.

Samples would be removed from a wet environment at the time of sample unloading making the dry sample conditions applicable.. Therefore dry sample results are the limiting case for all samples.

2. For the (f/s) approximation the maximum energy release rate is 5.35 E13 MeV/s or 8.57 watts.

3. Activities calculated in TS 18 are a better approximation of the actual activities being produced in fissionable materials than that used in TS 17. TS 17 used cumulative fission yields and TS 18 used individual fission yields with a time dependent activity buildup from production and decay. The activity calculations made by this method in TS 18 are generally higher than those estimated by the Nuclear Analysis 1.0 program.

4. The associated limiting fission rates in TS 18 are higher than those in TS 17, but are explained by the difference in the calculation model used. With this explanation and with activity results being generally greater than those from an independent computer based program, the resulting limiting fission rates are concluded to be acceptable for the performance of fueled experiments.

61